ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Measurement of clottability of fibrin polymers using magnetic orientation : The 40th annual conference on magnetism and magnetic materials (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 4708-4710 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Fibrin polymers, as a kind of diamagnetic material, are oriented parallel to the direction of magnetic fields. We investigated the polymerization of partially digested fibrinogens in an 8 T magnetic field in order to observe the clotting ability of various sizes of fibrinogen fractions using a magnetic orientation technique. We purified high-molecular weight fraction (F1) and low-molecular weight fraction from human fibrinogen (F2). Fibrin gels were formed in an 8 T magnetic field for 9 h, and transmittancies were measured to evaluate the degree of magnetic orientation. The results show that a lack at the C-terminal half of one Aα chain did not affect the magnetic orientation of fibrin. We also investigated the effect of the digestion of fibrinogen by plasmin on the magnetic orientation of fibrin. The result shows that partially digested fibrin molecules also orient in an 8 T magnetic field. However, the degree of magnetic orientation significantly decreases when fragment X and fragment Y appear. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.361647
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Catalytic activity of catalase under strong magnetic fields of up to 8 T : The 40th annual conference on magnetism and magnetic materials (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 4705-4707 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The question of whether or not magnetic fields affect enzymatic activity is of considerable interest in biomagnetics and biochemistry. This study focuses on whether magnetically related enzymatic activities can be affected by magnetic fields. We examined the effect of magnetic fields of up to 8 T on catalytic decomposition of hydrogen peroxide (H2O2). We observed changes in absorbance of reaction mixture of hydrogen peroxide and catalase at 240 nm, during and after magnetic field exposures. When the reaction mixture was not treated with nitrogen-gas bubbling, it was observed that the initial reaction rate of the reaction which was exposed to magnetic fields of up to 8 T was 50%–85% lower than the control data. This magnetic field effect was not observed, however, when the reaction mixture was bubbled with nitrogen gas to remove the dissolved oxygen molecules which were produced in the solution. We also measured concentration of dissolved oxygen which was produced by the decomposition of hydrogen peroxide. Dissolved oxygen concentration in the reaction mixture which was exposed to magnetic fields increased 20%–25% compared to the control solution. The results of the present study indicate that magnetic fields affect dynamic movement of oxygen bubbles which are produced in the reaction mixture by the decomposition of hydrogen peroxide, but not the catalytic activity of catalase itself. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.361646
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Bioluminescence under static magnetic fields : The 7th joint MMM-intermag conference on magnetism and magnetic materials (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 83 (1998), S. 6456-6458 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In the present study, the effect of magnetic fields on the emission of light by a living system was studied. The fireflies Hotaria parvula and Luciola cruciata were used as the bioluminescence systems. The firefly light organ was fixed at the edge of an optical fiber. The emitted light was introduced into a single-channel photon-counting system using an optical fiber. We measured both the spectrum of a constant light emission and, the time course of bioluminescence pulses. Two horizontal-type superconducting magnets, which produced 8 and 14 T magnetic fields at their center, were used as the magnetic-field generators. We also carried out an in vitro study of bioluminescence. The enzymatic activity of luciferase was measured under a 14 T magnetic field. We measured emission spectra of bioluminescence over the interval 500–600 nm at 25 °C in a stable emission state. It was observed that the peak wavelength around 550 nm shifted to 560 nm under a 14 T magnetic field. However, the effects of magnetic fields were not significant. Also, we measured the time course of emissions at 550 nm in a transient emission state. The rate in the light intensity under a 14 T magnetic field increased compared to the control. There is a possibility that the change in the emission intensities under a magnetic field is related to a change in the biochemical systems of the firefly, such as the enzymatic process of luciferase and the excited singlet state with subsequent light emission. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.367736
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Polymerization and dissolution of fibrin under homogeneous magnetic fields : The 7th joint MMM-intermag conference on magnetism and magnetic materials (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 83 (1998), S. 6453-6455 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We investigated whether or not a mutually compensating state of coagulation and fibrinolysis is changed by homogeneous magnetic fields. We used a superconducting magnet which produced magnetic fields of up to 14 T at its center. Fibrin polymerization over time, and the subsequent dissolution of the fibrin fiber network, were observed by measuring the optical absorbance of the mixture at 350 nm. A spectrophotometer with an external optical cell box in a superconducting magnet was used. We observed that the optical absorbance of the mixture at 350 nm increased during the fibrin-polymerization process, and decreased during the fibrinolytic processes. The optical absorbance was stable in the transient state between fibrin-polymerization and fibrinolytic processes. A magnetic field of 14 T increased the rate of the polymerization process by 55%–70% compared to the control group. On the other hand, the rate of the fibrinolytic process under a magnetic field at 14 T, increased by 27%–140% compared to the control. The results indicate that the magnetic orientation of fibrin fibers accelerated both the polymerization and the dissolution of fibrin fibers. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.367735
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Structure of water molecules under 14 T magnetic field : The 7th joint MMM-intermag conference on magnetism and magnetic materials (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 83 (1998), S. 6459-6461 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this study, we investigated the effects of strong magnetic fields of up to 14 T on the near-infrared spectrum of water molecules. We used a near-infrared spectrophotometer, which has an external optical cell box in a 14 T superconducting magnet. We measured the near-infrared spectrum of water in the range of 900–2000 nm by changing the optical path lengths from 0.1 to 100 mm. The peak wavelengths in the near-infrared spectrum in the range of 900–2000 nm of water, increased in length by 1–3 nm under a 14 T magnetic field. Also, we measured a near-infrared spectrum of glucose solutions under a magnetic field at 14 T to investigate the hydration of sugar. In contrast to the case of water, the peak wavelength of glucose solutions showed blueshift under a 14 T magnetic field. When the magnetic fields were changed from 0 to 14 T, the differential optical absorbance of the glucose solution at 958 nm increased compared to the controls. There is a possibility that the 14 T magnetic field affects the formation of hydrogen bonds of water molecules and the hydration of glucose molecules. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.367737
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Properties of diamagnetic fluid in high gradient magnetic fields : 38th Annual Conference on Magnetism and Magnetic Materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 7177-7179 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: This study focuses on the properties of diamagnetic fluid in static magnetic fields up to 8 T with the gradient of 50 T/m. We used a horizontal type of superconducting magnet with a bore 100 mm in diameter and 700 mm long. We observed the phenomenon that the surface of the water was pushed back by magnetic fields of higher gradients. Two "frozen'' cascades were formed at z=±50–80 mm; the surface of the water near the center of the magnet was parted, and the bottom of the water chamber appeared. The water level at both ends of the chamber was lifted up. In order to investigate the hydrodynamics of diamagnetic fluid in magnetic fields, we made a fluidic circuit with plastic tubing which passed through the superconducting magnet's bore. When magnetic fields in the center of the bore were changed from 0 to 8 T, the flow velocity of distilled water decreased, and the flow was stopped at 8 T. A stress analysis of diamagnetic fluid in magnetic fields was carried out to explain the mechanism of these phenomena. The hydrodynamics of diamagnetic fluid in ∼400 T2/m is able to compare with that of ferromagnetic fluid in weak magnetic fields. Studying the role of diamagnetic fluid in gradient magnetic fields is important in understanding the mechanism of biological effects of magnetic fields.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356686
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Effects of magnetic fields on fibrinolysis : 38th Annual Conference on Magnetism and Magnetic Materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 7162-7164 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In this study, we investigated the possible effects of magnetic fields on the fibrinolytic process. Fibrin dissolution was observed and the fibrinolytic activities were evaluated. First, fibrinolytic processes in magnetic fields were investigated by the fibrin plate method. We gathered solutions from the dissolved fibrin, and measured mean levels of fibrin degradation products (FDPs) in solutions. Mean levels of FDPs exposed to 8 T magnetic fields were higher than those not exposed to fields. Second, we carried out an experiment to understand how fibrin oriented in a magnetic field dissolves. FDPs in solutions of dissolved fibrins in fibrin plates were assayed. The result was that fibrin gels formed in a magnetic field at 8 T were more soluble than those not formed in a magnetic field. A model based on the diamagnetic properties of macromolecules was explained, and changes of protein concentrations in a solution in gradient magnetic fields were predicted.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356715
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Redistribution of dissolved oxygen concentration under magnetic fields up to 8 T : 38th Annual Conference on Magnetism and Magnetic Materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 7174-7176 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The influence of static magnetic fields on the behavior of oxygen dissolved in an aqueous solution was studied in order to clarify the interaction mechanism of dynamic movements of dissolved oxygen with magnetic fields and to broaden the basic understanding of biological effects of magnetic fields. A horizontal type of superconducting magnet with a bore 100 mm in diameter was used. A cylindrical chamber filled with distilled water was exposed to magnetic fields up to 8 T and a gradient of 50 T/m. The spatial distribution of oxygen concentration dissolved in water was measured by a dissolved oxygen meter. A clear redistribution of oxygen concentration was observed, and the dissolved oxygen concentration increased more than 10% around the center of the magnet.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356685
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Enzymatic oxidation-reduction processes under magnetic fields up to 8 T (abstract) : 38th Annual Conference on Magnetism and Magnetic Materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 7181-7181 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The question of whether magnetic fields affect enzymatic activities or not is of considerable interest in biochemistry and in biomagnetics. Xanthine oxidase, contained in liver, lungs, intestine, and other organs, catalyzes the degradation of hypoxanthine to xanthine, and xanthine to uric acid, which is the terminal waste of purine nucleotides in mammals. During the oxidation of xanthine, the enzyme releases superoxide anion radicals as intermediates which reduce ferricytochrome c (Fe3+). Superoxide anion, as well as any type of free radical, is also paramagnetic. The study is focused on whether these magnetically related enzymatic activities can be affected by magnetic fields. There is a possibility that free radicals, as intermediates, can be modified by magnetic fields of specific intensities. In our previously reported study, we examined a possible effect of magnetic fields up to 1.0 T on biochemical reaction catalyzed by xanthine oxidase, and obtained negative results. In the present abstract, we examine the effect of magnetic fields up to 8 T on this oxidation-reduction process. Reduced cytochrome c (Fe2+) has an absorption maximum at 550 nm which can be detected by a spectrophotometer. Xanthine oxidase was assayed by superoxide dismutase—inhibitable reduction of cytochrome c. We measured optical absorbance of reduced cytochrome c by superoxide anion which was produced by the reaction catalyzed by xanthine oxidase. The absorbances of the mixture exposed to an 8 T magnetic field at 25 °C were higher than control samples in the re-oxidation proces of cytochrome c. The results show that the 8 T magnetic fields altered the rate of reduction of cytochrome c by superoxide anion which was produced by the reaction catalyzed by xanthine oxidase. It may conclude that the electron transfer from xanthine to molecular oxygen or the transfer from superoxide anion to cytochrome c, can be affected by the magnetic fields up to 8 T.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356688
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Early embryonic development of frogs under intense magnetic fields up to 8 T : 38th Annual Conference on Magnetism and Magnetic Materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 7165-7167 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A possible influence of intense magnetic fields on the embryonic development of frogs was studied in reference to a potential hazard in magnetic resonance imaging technology. Some of the most serious hazardous effects that could be induced by intense magnetic fields are teratogenic effects on developing embryos. In the present experiment, the possible influence of intense magnetic fields up to 8 T on the early embryonic development of Xenopus laevis was studied. Embryos were exposed to magnetic fields up to 8 T for the period from the precleavage stage to neurula in a small glass vial. Embryos were then cultured in Brown–Caston's medium until the feeding-tadpole stage. No apparent teratogenic effects were observed when embryos were cultured for 20 h from the stage of uncleaved fertilized egg to the neurula stage under magnetic fields of 8 T. We conclude that static magnetic fields up to 8 T do not appreciably affect the rapid cleavage and the following cell multiplication and differentiation in Xenopus laevis. We have also studied the early embryonic development of Xenopus laevis in a 40 nT magnetic field, or 1/1000 of the earth's magnetic field, and obtained negative results. Thus, again under this very low magnetic field, fertilized eggs developed normally and formed tadpoles with no appreciable abnormality.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356716
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...