scholarly journals A short review on the influence of magnetic fields on neurological diseases

10.52586/s561 ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 181
Keyword(s):  
Magnetic Fields ◽  
Neurological Diseases ◽  
Short Review

scholarly journals Observational View of Magnetic Fields in Active Galactic Nuclei Jets

2016 ◽  
Vol 12 (S324) ◽  
pp. 149-156
Author(s):  
Talvikki Hovatta
Keyword(s):  
Black Hole ◽  
Magnetic Fields ◽  
Active Galactic Nuclei ◽  
Galactic Nuclei ◽  
Short Review ◽  
Relativistic Jets ◽  
The Past ◽  
Emission Models ◽  
Active Galactic Nuclei Jets ◽  
The Magnetic Field

AbstractAccording to the currently favored picture, relativistic jets in active galactic nuclei (AGN) are launched in the vicinity of the black hole by magnetic fields extracting energy from the spinning black hole or the accretion disk. In the past decades, various models from shocks to magnetic reconnection have been proposed as the energy dissipation mechanism in the jets. This paper presents a short review on how linear polarization observations can be used to constrain the magnetic field structure in the jets of AGN, and how the observations can be used to constrain the various emission models.

scholarly journals T Tauri stars: magnetic fields and planets

2021 ◽  
Vol 2 (1) ◽  
pp. 9-20
Author(s):  
Konstantin Grankin
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Large Scale ◽  
Magnetic Coupling ◽  
Short Review ◽  
T Tauri Stars ◽  
Young Stars ◽  
Doppler Imaging ◽  
Hot Jupiters ◽  
T Tauri

In this short review we present the results of a study of the large-scale magnetic topologies of T Tauri stars (TTS). A small spectropolarimetric survey of 8 young stars was carried out within two international projects MaPP (Magnetic Protostars and Planets) and MaTYSSE (Magnetic Topologies of Young Stars and the Survival of massive close-in Exoplanets) between 2009 and 2016. For each of our targets we reconstructed the brightness map and the magnetic field topology using Zeeman–Doppler imaging (ZDI). This review contains a brief description of spectropolarimetricdata, the ZDI method, one example of the reconstruction of brightness and magnetic maps, and the properties of magnetic fields of 8 TTS. Our results suggest that AA Tau and LkCa 15 interact with their disks in the propeller mode when their rotation is actively slowed by the star/disk magnetic coupling. We find that magnetic fields of some TTS are variable on a time scale of a few years and are thus intrinsically nonstationary. We report on the detection of a giant exoplanet around V830 Tau and TAP 26. These two new detections suggest that the type II disk migration is efficient at generating newborn hot Jupiters (hJs) around young TTS. The result of our survey is compared to the global picture of magnetic field properties of twenty TTS in the Hertzsprung–Russell diagram. The comparison shows that WTTS exhibit a wider range of field topologies as compared to CTTS, and that magnetic fields of all TTS (CTTS and WTTS as a whole) are mostly poloidal and axisymmetric when they are mostly convective and cooler than 4300 K. This needs to be confirmed with a larger sample of stars.

scholarly journals Magnetohydrodynamics of an active region

1968 ◽  
Vol 35 ◽  
pp. 93-107 ◽  
Author(s):  
H. U. Schmidt
Keyword(s):  
Electrical Conductivity ◽  
Active Region ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Intermediate State ◽  
Short Review ◽  
The Sun ◽  
Infinite Conductivity

The dynamics of the magnetic fields which are imbedded into the non-stationary outer layers of the Sun show many facets of interest to observers and theoreticians alike. In a short review I can only deal with a small number of them and occasionally glance at some others. I hate to call these magnetic fields frozen into a matter which is rather in a boiling state, but the electrical conductivity in these layers is high enough to keep matter and magnetic flux together for rather long times, so that we can discuss the most important questions within the framework of magnetohydrodynamics with infinite conductivity. I will first talk mainly about the layers below the photosphere, where the matter controls the motion of the field, secondly about the intermediate state near the photosphere, where matter and field have comparable energy, and finally about the upper layers where the field controls the material motion.

scholarly journals Magnetic Fields Trump Oxygen in Controlling the Death of Erythro-Leukemia Cells

2019 ◽  
Vol 9 (24) ◽  
pp. 5318
Author(s):  
Ying Li ◽  
Paul Héroux
Keyword(s):  
Cell Death ◽  
Magnetic Fields ◽  
Cancer Cells ◽  
Human Cancer ◽  
Neurological Diseases ◽  
Zero Field ◽  
Electromagnetic Environment ◽  
Human Environment ◽  
Human Cancer Cells

Expansions in power and telecommunications systems have created a new electromagnetic environment. Here, we compare the death rate of human cancer cells in vitro in the pre-industrial electromagnetic environment of the past (“Zero Field”) with that of an electromagnetic environment typical of contemporary human exposures (“Incubator Field”). A cell incubator provides magnetic fields comparable to those in the current human environment. Steel shields divert those same fields away from cell preparations in the “pre-industrial” assays. Large changes in oxygen levels are provided by nitrogen or atmospheric gas over the cell cultures. Human cancer cells are then separated according to three categories: necrotic, early apoptotic, or late apoptotic. The results are compiled for two variables, magnetic field and oxygen, in 16 different situations (“Transitions”) likely to occur in the human body under present living conditions. We find that magnetic fields are a more powerful determinant of cell death than oxygen, and induce death by different mechanisms. This has important implications for the reproducibility of in vitro biological experiments focusing on cell survival or metabolism, and for public health. The rate and mechanisms of cell death are critical to many chronic human ailments such as cancer, neurological diseases, and diabetes.

scholarly journals Role of Botulinum toxin injection in neurological problems: A Short Review

2016 ◽  
Vol 12 (1) ◽  
pp. 3-7
Author(s):  
Isha Dhungana ◽  
Prabin Shrestha
Keyword(s):  
Botulinum Toxin ◽  
Success Rate ◽  
Neurological Disorders ◽  
Neurological Diseases ◽  
Botulinum Toxin Injection ◽  
Symptomatic Treatment ◽  
Short Review ◽  
Medical Problems ◽  
Good Success Rate

Botulinum Toxin (BoNT), a neurotoxin known for many years for its lethal nature has been in use for many cosmetic purposes for last many years. Its use in many medical problems especially chronic neurological problems has been well established in recent years. BoNT is a useful symptomatic treatment for many neurological disorders, and is emerging as one of the leading modes of treatments in the new subspecialty in neurology called “Interventional neurology.” We have also been using BoNT regularly for therapeutic purposes in different neurological diseases with good success rate for last few years. We think use of BoNT-A needs to be encouraged in our country to provide relief to the patients suffering from many of the chronic disabling neurological problems.Nepal Journal of Neuroscience 12:3-7, 2015

Cardiac Biomarkers in Stroke, Alzheimer’s Disease, and Other Dementia. Are They of Use? A Brief Overview of Data from Recent Investigations

2020 ◽  
Vol 19 ◽  
Author(s):  
Shahzad Khan ◽  
Mohammad Amjad Kamal
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Clinical Trials ◽  
Neurological Diseases ◽  
Short Review ◽  
The Other ◽  
Cardiac Biomarkers ◽  
Cardiac Diseases ◽  
Primary Condition ◽  
Diagnosis And Prognosis

: Conventionally cardiac biomarkers are recognized as an essential tool to investigate the presence or progression of various cardiovascular diseases. However, in recent years data from several clinical trials have successfully sorted out the utility of cardiac biomarkers in diseases that are not primarily regarded as “cardiac diseases,” especially neurological diseases. Results of freshly published trials have endorsed the use of cardiac biomarkers in various forms of stroke and dementia, including Alzheimer’s disease. Alzheimer’s disease is also one of the other CNS conditions where measuring cardiac biomarkers have found to be useful. Cardiac biomarkers can be helpful in two ways. Firstly, to assess the secondary involvement of the heart during the progression of the primary disease. Secondly, they can be useful in the diagnosis and prognosis of the primary condition itself. In this short review, we have collected encouraging results from recent studies that show the importance of the most widely recognized cardiac biomarkers in two of the most prominent neurological diseases of the current world, i.e., stroke and dementia.

Calculated Coronal Magnetic Fields and Their Comparison with the Coronal Structures as Observed during Five Solar Eclipses

1994 ◽  
Vol 144 ◽  
pp. 559-564
Author(s):  
P. Ambrož ◽  
J. Sýkora
Keyword(s):  
Magnetic Field ◽  
Solar Cycle ◽  
Magnetic Fields ◽  
Solar Corona ◽  
Coronal Magnetic Field ◽  
Coronal Magnetic Fields ◽  
Solar Eclipses ◽  
Coronal Structures

AbstractWe were successful in observing the solar corona during five solar eclipses (1973-1991). For the eclipse days the coronal magnetic field was calculated by extrapolation from the photosphere. Comparison of the observed and calculated coronal structures is carried out and some peculiarities of this comparison, related to the different phases of the solar cycle, are presented.

Radio Measurements of Coronal Magnetic Fields

1994 ◽  
Vol 144 ◽  
pp. 21-28 ◽  
Author(s):  
G. B. Gelfreikh
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Solar Corona ◽  
Active Regions ◽  
High Sensitivity ◽  
Coronal Magnetic Field ◽  
Transverse Magnetic ◽  
Radio Sources ◽  
Radio Waves ◽  
Solar Active Regions

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy of Sciences — RATAN-600. This proved possible due to good wavelength coverage, multichannel spectrographs observations and high sensitivity to polarization of the instrument. Besides direct measurements of the strength of the magnetic fields in some cases the peculiar parameters of radio sources, such as very steep spectra and high brightness temperatures provide some information on a very complicated local structure of the coronal magnetic field. Of special interest are the results found from combined RATAN-600 and large antennas of aperture synthesis (VLA and WSRT), the latter giving more detailed information on twodimensional structure of radio sources. The bulk of the data obtained allows us to investigate themagnetospheresof the solar active regions as the space in the solar corona where the structures and physical processes are controlled both by the photospheric/underphotospheric currents and surrounding “quiet” corona.

Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Ultra Violet ◽  
Active Regions ◽  
Morphological Properties ◽  
Energy Storage And Conversion ◽  
The Sun ◽  
X Rays ◽  
The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

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