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Rotating magnetic field inhibits Aβ protein aggregation and alleviates cognitive impairment in Alzheimer’s disease mice
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作者 Ruo-Wen Guo Wen-Jing Xie +5 位作者 Biao Yu Chao Song Xin-Miao Ji Xin-Yu Wang Mei Zhang Xin Zhang 《Zoological Research》 SCIE CSCD 2024年第4期924-936,共13页
Amyloid beta(Aβ)monomers aggregate to form fibrils and amyloid plaques,which are critical mechanisms in the pathogenesis of Alzheimer’s disease(AD).Given the important role of Aβ1-42 aggregation in plaque formation... Amyloid beta(Aβ)monomers aggregate to form fibrils and amyloid plaques,which are critical mechanisms in the pathogenesis of Alzheimer’s disease(AD).Given the important role of Aβ1-42 aggregation in plaque formation,leading to brain lesions and cognitive impairment,numerous studies have aimed to reduce Aβaggregation and slow AD progression.The diphenylalanine(FF)sequence is critical for amyloid aggregation,and magnetic fields can affect peptide alignment due to the diamagnetic anisotropy of aromatic rings.In this study,we examined the effects of a moderate-intensity rotating magnetic field(RMF)on Aβaggregation and AD pathogenesis.Results indicated that the RMF directly inhibited Aβamyloid fibril formation and reduced Aβ-induced cytotoxicity in neural cells in vitro.Using the AD mouse model APP/PS1,RMF restored motor abilities to healthy control levels and significantly alleviated cognitive impairments,including exploration and spatial and non-spatial memory abilities.Tissue examinations demonstrated that RMF reduced amyloid plaque accumulation,attenuated microglial activation,and reduced oxidative stress in the APP/PS1 mouse brain.These findings suggest that RMF holds considerable potential as a non-invasive,high-penetration physical approach for AD treatment. 展开更多
关键词 lzheimer’s disease Rotating magnetic field Amyloid-β Cognitive function Alzheimer’s disease animal models
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An Explanation of the Temperature-Dependent Upper Critical Field Data of H3S on the Basis of the Thermodynamics of a Superconductor in a Magnetic Field
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作者 Gulshan Prakash Malik 《World Journal of Condensed Matter Physics》 CAS 2024年第3期45-50,共6页
Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtai... Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtained by Talantsev (2019) in an approach based on an ingenious mix of the Ginzberg-Landau (GL), the Werthamer, Helfand and Hohenberg (WHH), and the Gor’kov, etc., theories which have individually been employed for the same purpose for a long time. Up to the lowest temperature (TL) in each of these data-sets, similarly accurate fits have also been obtained by Malik and Varma (2023) in a radically different approach based on the Bethe-Salpeter equation (BSE) supplemented by the Matsubara and the Landau quantization prescriptions. For T TL, however, while the (GL, WHH, etc.)-based approach leads to Hc2(0) ≈ 100 T, the BSE-based approach leads to about twice this value even at 1 K. In this paper, a fit to one of the said data-sets is obtained for the first time via a thermodynamic approach which, up to TL, is as good as those obtained via the earlier approaches. While this is interesting per se, another significant result of this paper is that for T TL it corroborates the result of the BSE-based approach. 展开更多
关键词 H3s Upper Critical field (Hc2) Variation of Hc2 with Temperature Clausius-Clapeyron equation in a magnetic field Behavior of Hc2 for Temperatures Close to 0 K
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A Simple Mechanism for Generating a Geomagnetic Field
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作者 Oleg Vladimirovich Styazhkin 《Open Journal of Applied Sciences》 2024年第9期2580-2591,共12页
On the basis of the ideal gas model, the polarization of charges in the mantle was obtained, a physical and mathematical model was constructed, and estimated calculations of the dipole mode of the Earth’s magnetic fi... On the basis of the ideal gas model, the polarization of charges in the mantle was obtained, a physical and mathematical model was constructed, and estimated calculations of the dipole mode of the Earth’s magnetic field were performed, taking into account the speed of its angular rotation, the parameters of density and temperature, the chemical composition, the ionization potential, the dielectric constant and the percentage of the main chemical compounds of the mantle substance. 展开更多
关键词 Physical Parameters of the Earth’s Mantle Maxwell-Boltzmann statistics Phonon Gas Thermal Ionization Electron-Hole Polarization Electron-Hole Recombination Earth’s magnetic field Dipole Mode of the magnetic field
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Chaotic Motion Analysis for a Coupled Magnetic-Flow-Mechanical Model of the Rectangular Conductive Thin Plate
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作者 Xinzong Wang Xiaofang Kang Qingguan Lei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期1749-1771,共23页
The chaotic motion behavior of the rectangular conductive thin plate that is simply supported on four sides by airflow andmechanical external excitation in a magnetic field is studied.According to Kirchhoff’s thin pl... The chaotic motion behavior of the rectangular conductive thin plate that is simply supported on four sides by airflow andmechanical external excitation in a magnetic field is studied.According to Kirchhoff’s thin plate theory,considering geometric nonlinearity and using the principle of virtualwork,the nonlinearmotion partial differential equation of the rectangular conductive thin plate is deduced.Using the separate variable method and Galerkin’s method,the system motion partial differential equation is converted into the general equation of the Duffing equation;the Hamilton system is introduced,and the Melnikov function is used to analyze the Hamilton system,and obtain the critical surface for the existence of chaos.The bifurcation diagram,phase portrait,time history response and Poincarémap of the vibration system are obtained by numerical simulation,and the correctness is demonstrated.The results showthatwhen the ratio of external excitation amplitude to damping coefficient is higher than the critical surface,the system will enter chaotic state.The chaotic motion of the rectangular conductive thin plate is affected by different magnetic field distributions and airflow. 展开更多
关键词 Rectangular conductive thin plate CHAOTIC AIRFLOW magnetic field Melnikov function Galerkin’s method
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Ultra-high-field magnetic resonance:Why and when? 被引量:1
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作者 Ewald Moser 《World Journal of Radiology》 CAS 2010年第1期37-40,共4页
This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current li... This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher. 展开更多
关键词 Alzheimer’s disease Brain tumors CARTILAGE Functional magnetic REsONANCE imaging magnetic REsONANCE magnetic REsONANCE spectroscopy Multiple sCLEROsIs Ultra-high field magnetic REsONANCE methods
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Changes of auditory evoked magnetic fields in patients after acute cerebral infarction using magnetoencephalography 被引量:1
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作者 Zhanyong Sun Chunfeng Song +7 位作者 Jilin Sun Ling Li Yanhong Dong Jianhua Wang Jie Wu Wenzhu Cui Yujin Wu Peiyuan Lv 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1906-1913,共8页
Auditory evoked magnetic fields were recorded from 15 patients with acute cerebral infarction and 11 healthy volunteers using magnetoencephalography.The auditory stimuli of 2 kHz pure tone were binaurally presented wi... Auditory evoked magnetic fields were recorded from 15 patients with acute cerebral infarction and 11 healthy volunteers using magnetoencephalography.The auditory stimuli of 2 kHz pure tone were binaurally presented with an interstimulus interval of 1 second.The intensity of stimuli was 90 dB and the stimulus duration was 8 ms.The results showed that the M100 was the prominent response, peaking approximately 100 ms after stimulus onset in all subjects.It originated from the area close to Heschl’s gyrus.In the patient group,the peak latency of M100 responses was significantly prolonged,and the mean strength of equivalent current dipole was significantly smaller in the affected hemisphere.The three-dimensional inter-hemispheric difference of the M100 positions was increased in the patient group.Our experimental findings suggested that impairment of cerebral function in patients with acute ischemic stroke can be detected using magnetoencephalography with the higher spatial resolution and temporal resolution.Magnetoencephalography could provide objective and sensitive indices to estimate auditory cortex function in patients with acute cerebral infarction. 展开更多
关键词 acute cerebral infarction cerebral ischemia magnetOENCEPHALOGRAPHY auditory evoked magnetic fields equivalent current dipole Heschl’s gyrus brain functional impairment nerve injury regeneration neural regeneration
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Extremely low frequency electromagnetic fields stimulation modulates autoimmunity and immune responses:a possible immuno-modulatory therapeutic effect in neurodegenerative diseases 被引量:2
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作者 Fabio Guerriero Giovanni Ricevuti 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第12期1888-1895,共8页
Increasing evidence shows that extremely low frequency electromagnetic fields(ELF-EMFs) stimulation is able to exert a certain action on autoimmunity and immune cells. In the past, the efficacy of pulsed ELFEMFs in ... Increasing evidence shows that extremely low frequency electromagnetic fields(ELF-EMFs) stimulation is able to exert a certain action on autoimmunity and immune cells. In the past, the efficacy of pulsed ELFEMFs in alleviating the symptoms and the progression of multiple sclerosis has been supported through their action on neurotransmission and on the autoimmune mechanisms responsible for demyelination. Regarding the immune system, ELF-EMF exposure contributes to a general activation of macrophages, resulting in changes of autoimmunity and several immunological reactions, such as increased reactive oxygen species-formation, enhanced phagocytic activity and increased production of chemokines. Transcranial electromagnetic brain stimulation is a non-invasive novel technique used recently to treat different neurodegenerative disorders, in particular Alzheimer's disease. Despite its proven value, the mechanisms through which EMF brain-stimulation exerts its beneficial action on neuronal function remains unclear. Recent studies have shown that its beneficial effects may be due to a neuroprotective effect on oxidative cell damage. On the basis of in vitro and clinical studies on brain activity, modulation by ELF-EMFs could possibly counteract the aberrant pro-inflammatory responses present in neurodegenerative disorders reducing their severity and their onset. The objective of this review is to provide a systematic overview of the published literature on EMFs and outline the most promising effects of ELF-EMFs in developing treatments of neurodegenerative disorders. In this regard, we review data supporting the role of ELF-EMF in generating immune-modulatory responses, neuromodulation, and potential neuroprotective benefits. Nonetheless, we reckon that the underlying mechanisms of interaction between EMF and the immune system are still to be completely understood and need further studies at a molecular level. 展开更多
关键词 electromagnetic fields Alzheimer's disease transcranial magnetic stimulation autoimmunity immunomodulation
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Earth’s Magnetic Field—The Key to Global Warming 被引量:1
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作者 Bjarne Lorenzen 《Journal of Geoscience and Environment Protection》 2019年第7期25-38,共14页
It is commonly known that the climate debate suffers due to a lack of knowledge about the cause and effect relationship between a number of climatic temperature variations that have occurred in history without being a... It is commonly known that the climate debate suffers due to a lack of knowledge about the cause and effect relationship between a number of climatic temperature variations that have occurred in history without being able to blame human emission of greenhouse gas in any way. Only when we are willing to give up the idea that there is a geodynamo deep inside of the Earth being responsible for the Earth’s magnetic field and when we get back to the idea that the origin of the magnetic field is simply ferromagnetic, will it be possible to establish two different cause and effect connections that are suitable to explain why there is an acknowledged coincidence between climatic temperature variations and an intensive, proportional variation in the strength of the Earth’s magnetic field. Such insight may easily prove to be decisive at a time when many people can no longer differentiate between politics, mass hysteria, presumptions and actual knowledge. When there are requirements that a solution to climatic temperature variations must contain the solution to the coincidence mentioned, two possible scenarios exist. The one possibility (although not very likely) that is suitable to solve the mysterious coincidence is that mainly the northern part of the Atlantic Ocean is heated from within (from the interior of the Earth) and that variations in the Earth’s emission of heat cause primarily all of Europe to have witnessed warm winters for decades. The one possible cause and effect connection may (in theory) be that inner heat in the Earth’s crust can loosen frozen, ferromagnetic structures, thereby drive the Earth’s ferromagnetic, magnetic field to restructure and be reorganised from periodically being a chaotic, magnetic field to periodically being a well-structured, ferromagnetic field. The connection between magnetism and thermal impact is already commonly known. The other and somewhat more likely cause and effect connection is building on Henrik Svensmark’s (and teams) theory that says that variations in the cosmic radiation reaching the Earth depend on the strength of the Sun’s magnetic field and that this radiation contributes to creating aerosols, thereby variations in the cloud formation. Solar storms contribute to temporarily strengthening the Earth’s magnetic field. The question is whether these contributions could also periodically have a long-term effect on the Earth’s magnetic field. In that case, this may explain the reason for the above-mentioned coincidence. 展开更多
关键词 Earth’s magnetic field GEODYNAMO Global WARMING
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Pressure Tuning of Magnetism and Drastic Increment of Thermal Conductivity under Applied Magnetic Field in HgCr_2S_4
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作者 顾川川 陈绪亮 +4 位作者 沈晨 凌浪生 皮雳 杨昭荣 张裕恒 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期137-140,共4页
HgCr2S4 is a typical compound manifesting competing ferromagnetic (FM) and antiferromagnetic (AFM) exchanges as well as strong spin-lattice coupling. Here we study these effects by intentionally choosing a combina... HgCr2S4 is a typical compound manifesting competing ferromagnetic (FM) and antiferromagnetic (AFM) exchanges as well as strong spin-lattice coupling. Here we study these effects by intentionally choosing a combination of magnetization under external hydrostatic pressure and thermal conductivity at various magnetic fields. Upon applying pressure up to 10 kbar at 1 kOe, while the magnitude of magnetization reduces progressively, the AFM ordering temperature TN enhances concomitantly at a rate of about 1.5 K/kbar. Strikingly, at lO kOe the field polarized FM state is found to be driven readily back to an AFM one even at only 5kbar. In addition, the thermal conductivity exhibits drastic increments at various fields in the temperature range with strong spin fluctuations, reaching about 30% at 50 kOe. Consequently, the results give new experimental evidence of spin-lattice coupling. Apart from the colossal magnetoeapacitance and colossal magnetoresistance reported previously, the findings here may enable new promising functionalities for potential applications. 展开更多
关键词 of on as Is AFM in Pressure Tuning of magnetism and Drastic Increment of Thermal Conductivity under Applied magnetic field in HgCr2s4
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Numerical Solution for a Similar Flow between Two Disks in the Presence of a Magnetic Field
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作者 Sajjad Hussain Muhammad Anwar Kamal +3 位作者 Farooq Ahmad Muhammad Ali Muhammad Shafique Sifat Hussain 《Applied Mathematics》 2013年第8期1163-1167,共5页
Numerical solutions are obtained for non-steady, incompressible fluid flow between two parallel disks which at time t are separated by a distance H(1-αt)1/2 and a magnetic field proportional to B0(1-αt) -1/2 is appl... Numerical solutions are obtained for non-steady, incompressible fluid flow between two parallel disks which at time t are separated by a distance H(1-αt)1/2 and a magnetic field proportional to B0(1-αt) -1/2 is applied perpendicular to the disks where H denotes a representative length, BO denotes a representative magnetic field and α-1 denotes a representative time. Similarity transformations are used to convert the governing partial differential equations of motion in to ordinary differential form. The resulting ordinary differential equations are solved numerically using SOR method, Richardson extrapolation and Simpson’s (1/3) Rule. Our numerical scheme is straightforward, efficient and easy to program. 展开更多
关键词 Numerical solution similar FLOW NEWTONIAN Fluid magnetic field Reynold’s Number
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Origin of Magnetic Fields of Stellar Objects in the Universe Based on the 5D Projection Theory
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作者 Peter C. W. Fung K. W. Wong 《Journal of Modern Physics》 2017年第4期668-746,共79页
Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D p... Beginning with a 5D homogeneous universe [1], we have provided a plausible explanation of the self-rotation phenomenon of stellar objects previously with illustration of large number of star samples [2], via a 5D-4D projection. The origin of such rotation is the balance of the angular momenta of stars and that of positive and negative charged e-trino pairs, within a 3D &otimes;1D?void of the stellar object, the existence of which is based on conservation/parity laws in physics if one starts with homogeneous 5D universe. While the in-phase e-trino pairs are proposed to be responsible for the generation of angular momentum, the anti-phase but oppositely charge pairs necessarily produce currents. In the 5D to 4D projection, one space variable in the 5D manifold was compacted to zero in most other 5D theories (including theories of Kaluza-Klein and Einstein [3] [4]). We have demonstrated, using the Fermat’s Last Theorem [5], that for validity of gauge invariance at the 4D-5D boundary, the 4th space variable in the 5D manifold is mapped into two current rings at both magnetic poles as required by Perelman entropy mapping;these loops are the origin of the dipolar magnetic field. One conclusion we draw is that there is no gravitational singularity, and hence no black holes in the universe, a result strongly supported by the recent discovery of many stars with masses well greater than 100 solar mass [6] [7] [8], without trace of phenomena observed (such as strong gamma and X ray emissions), which are supposed to be associated with black holes. We analyze the properties of such loop currents on the 4D-5D boundary, where Maxwell equations are valid. We derive explicit expressions for the dipolar fields over the whole temperature range. We then compare our prediction with measured surface magnetic fields of many stars. Since there is coupling in distribution between the in-phase and anti-phase pairs of e-trinos, the generated mag-netic field is directly related to the angular momentum, leading to the result that the magnetic field can be expressible in terms of only the mechanical variables (mass M, radius R, rotation period P)of a star, as if Maxwell equations are “hidden”. An explanation for the occurrence of this “un-expected result” is provided in Section (7.6). Therefore we provide satisfactory answers to a number of “mysteries” of magnetism in astrophysics such as the “Magnetic Bode’s Relation/Law” [9] and the experimental finding that B-P graph in the log-log plot is linear. Moreover, we have developed a new method for studying the relations among the data (M, R, P) during stellar evolution. Ten groups of stellar objects, effectively over 2000 samples are used in various parts of the analysis. We also explain the emergence of huge magnetic field in very old stars like White Dwarfs in terms of formation of 2D Semion state on stellar surface and release of magnetic flux as magnetic storms upon changing the 2D state back to 3D structure. Moreover, we provide an explanation, on the ground of the 5D theory, for the detection of extremely weak fields in Venus and Mars and the asymmetric distribution of magnetic field on the Martian surface. We predict the equatorial fields B of the newly discovered Trappist-1 star and the 6 nearest planets. The log B?&minus;?log P graph for the 6 planets is linear and they satisfy the Magnetic Bode’s relation. Based on the above analysis, we have discovered several new laws of stellar magnetism, which are summarized in Section (7.6). 展开更多
关键词 5D Projection Theory Fermat’s Last Theorem Perelman’s Mappings self-Rotation Dipolar magnetic field of stars LAWs of sTELLAR magnetism LAWs of sTELLAR Angular Momentum magnetic Bode’s Law NON-EXIsTENCE of Gravitational singularity semion state of Atoms in sTELLAR surface magnetic storm Planetary magnetic field Maxwell Equations at 4D-5D Boundary magnetic fields of the Trappist-1 system
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Constraining evolution of magnetic field strength in the dissipation region of two BL Lac objects
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作者 Xu-Liang Fan Da-Hai Yan +1 位作者 Qing-Wen Wu Xu Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第12期351-356,共6页
With the assumption that the optical variability timescale is dominated by the cooling time of the synchrotron process for BL Lac objects,we estimate time dependent magnetic field strength of the emission region for t... With the assumption that the optical variability timescale is dominated by the cooling time of the synchrotron process for BL Lac objects,we estimate time dependent magnetic field strength of the emission region for two BL Lac objects.The average magnetic field strengths are consistent with those estimated from core shift measurement and spectral energy distribution modelling.Variation of magnetic field strength in the dissipation region is discovered.Variability of flux and magnetic field strength shows no clear correlation,which indicates the variation of magnetic field is not the dominant reason of the variability origin.The evolution of magnetic field strength can provide another approach to constrain the energy dissipation mechanism in jets. 展开更多
关键词 BL Lacertae objects:general BL Lacertae objects:individual(s50716%PLUs%714 BL Lacertae) galaxies:magnetic fields
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Secular Effect of Geomagnetic Field and Gravitational Waves on Earth’s Satellite Orbits
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作者 M. H. A. Youssef 《Journal of Applied Mathematics and Physics》 2019年第8期1697-1705,共9页
In this work we study the perturbation and the change in the orbital elements due to the earth’s magnetic field and the gravitational waves. The acceleration components are derived in the radial, transverse to it and... In this work we study the perturbation and the change in the orbital elements due to the earth’s magnetic field and the gravitational waves. The acceleration components are derived in the radial, transverse to it and normal to the orbital plane. The equation for the rates of variation of the elements is formed and solved to find the secular variation in the element for polar and equatorial satellites. 展开更多
关键词 GRAVITATIONAL WAVEs Earth’s magnetic field PERTURBATIONs ORBITAL MECHANICs
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Tunneling of Relativistic Bosons Induced by Magnetic Fields in the Magnetar’s Crust
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作者 Marina-Aura Dariescu Ciprian Dariescu Denisa-Andreea Mihu 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第10期26-29,共4页
The present work is devoted to the study of bosons evolving in the frozen magnetar's crust endowed with an ultra-strong magnetic field orthogonal to an electric field, both described by periodic functions. We discuss... The present work is devoted to the study of bosons evolving in the frozen magnetar's crust endowed with an ultra-strong magnetic field orthogonal to an electric field, both described by periodic functions. We discuss the quantum tunneling process through the one-dimensional potential barrier along Oz. The solutions to the Klein- Gordon equation are expressed in terms of Mathieu's functions which, for computable particle's energy range, are turning from oscillatory to exponentially growing modes along Oz. Within the Jeffreys Wentzel Kramers- Brillouin framework, the transmission coefficient is computed for the particle momentum in the middle of the instability range. 展开更多
关键词 Tunneling of Relativistic Bosons Induced by magnetic fields in the magnetar’s Crust
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Dependence of Gravity Induced Absorption Changes on the Earth’s Magnetic Field as Measured during Parabolic Flight Campaigns
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作者 Werner Schmidt 《Journal of Modern Physics》 2013年第11期1546-1553,共8页
Various spectroscopic experiments performed on the AIRBUS ZERO G—located in Bordeaux, France—in the years 2002 to 2012 exhibit minute optical reflection/absorption changes (GIACs) as a result of gravitational change... Various spectroscopic experiments performed on the AIRBUS ZERO G—located in Bordeaux, France—in the years 2002 to 2012 exhibit minute optical reflection/absorption changes (GIACs) as a result of gravitational changes between 0 and 1.8 g in various biological species such as maize, oats, Arabidopsis and particularly Phycomyces sporangiophores. During a flight day, the AIRBUS ZERO G conducts 31 parabolas, each of which lasts about three minutes including a period of 22 s of weightlessness. So far, we participated in 11 parabolic flight campaigns including more than 1000 parabolas performing various kinds of experiments. During our campaigns, we observed an unexplainable variability of the measuring signals (GIACs). Using GPS-positioning systems and three dimensional magnetic field sensors, these finally were traced back to the changing earth’s magnetic field associated with the various flight directions. This is the first time that the interaction of gravity and the Earth’ magnetic field in the primary induction process in living system has been observed. 展开更多
关键词 MDWs(Micro Dual Wavelength spectrometer) GIAC(Gravity Induced Absorption Change) AIRBUs-300-ZERO-G Parabolic Flight Micro-and Hypergravity Three Dimensional Earth’s magnetic field Global Positioning system(GPs) Google Earth
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Mechanisms of Avian Magnetic Orientation 被引量:1
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作者 Joshua Dominic Rizak 车轶 《Zoological Research》 CAS CSCD 北大核心 2009年第2期221-224,共4页
Among the most fascinating mysteries of life is the interaction between biological systems and the earth's magnetic field. Although earth's magnetism may have an under appreciated role in biological interpretations,... Among the most fascinating mysteries of life is the interaction between biological systems and the earth's magnetic field. Although earth's magnetism may have an under appreciated role in biological interpretations, it has been most extensively studied in the processes of avian orientation and migration. Many species of bird are known to have behavioral responses to the earth's and artificial magnetic fields. These responses may be mediated by a number of potential magneto-biochemical processes. The two most commonly investigated include a magnetosensitive magnetite rich region in the upper beak area and a photo/magnetoreception process in the eyes of various bird species. In addition to external magnetic stimuli, recent findings in visually restricted birds have described a hemispherically lateralized interpretation of this information within the brain. Even with these findings, a considerable amount of work is needed to clarify what information is processed and how it is used to create the bird's magnetic compass. This review focuses these recently published findings as a means to assess this intriguing phenomenon. 展开更多
关键词 AVIAN Earth's magnetic field ORIENTATION
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A Dynamical Approach to the Explanation of the Upper Critical Field Data of Compressed H3S
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作者 Gulshan Malik Vijaya S. Varma 《World Journal of Condensed Matter Physics》 2023年第3期79-89,共11页
Excellent fits were obtained by Talantsev (MPLB 33, 1950195, 2019) to the temperature (T)-dependent upper critical field (H<sub>c</sub><sub>2</sub>(T)) data of H<sub>3</sub>S report... Excellent fits were obtained by Talantsev (MPLB 33, 1950195, 2019) to the temperature (T)-dependent upper critical field (H<sub>c</sub><sub>2</sub>(T)) data of H<sub>3</sub>S reported by Mozaffari et al. [Nature Communications 10, 2522 (2019)] by employing four alternative phenomenological models, each of which invoked two or more properties from its sample-specific set S<sub>1</sub> = {T<sub>c</sub>, gap, coherence length, penetration depth, jump in sp.ht.} and a single value of the effective mass (m*) of an electron. Based on the premise that the variation of H<sub>c</sub><sub>2</sub>(T) is due to the variation of the chemical potential μ(T), we report here fits to the same data by employing a T-, μ- and m*-dependent equation for H<sub>c</sub><sub>2</sub>(T) and three models of μ(T), viz. the linear, the parabolic and the concave-upward model. For temperatures up to which the data are available, each of these provides a good fit. However, for lower values of T, their predictions differ. Notably, the predicted values of H<sub>c</sub><sub>2</sub>(0) are much higher than in any of the models dealt with by Talantsev. In sum, we show here that the addressed data are explicable in a framework comprising the set S<sub>2</sub> = {μ, m*, interaction parameter λ<sub>m</sub>, Landau index N<sub>L</sub>}, which is altogether different from S<sub>1</sub>. 展开更多
关键词 Compressed H<sub>2sub>s Upper Critical magnetic field Pairing Equation Incorporating Temperature Chemical Potential and magnetic field Temperature Dependence of the Chemical Potential
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山东平原M_(S)5.5地震前岩石圈磁场异常变化及发震机理
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作者 张海洋 《大地测量与地球动力学》 CSCD 北大核心 2024年第9期892-898,904,共8页
基于冀鲁交界地区2020~2023年连续4期的流动地磁观测资料,分析区域岩石圈磁场时空变化特征及其与2023-08-06山东平原M_(S)5.5地震的关系,并结合岩石磁学的实验室结果和断层亚失稳理论,探讨平原地震前的亚失稳特征及发震机理。结果表明:1... 基于冀鲁交界地区2020~2023年连续4期的流动地磁观测资料,分析区域岩石圈磁场时空变化特征及其与2023-08-06山东平原M_(S)5.5地震的关系,并结合岩石磁学的实验室结果和断层亚失稳理论,探讨平原地震前的亚失稳特征及发震机理。结果表明:1)研究区岩石圈磁场时空变化特征在平原地震前有较为明显的异常反映,2020~2023年震中附近始终存在水平矢量的弱化区,并随着时间推移,出现水平矢量的弱化区逐渐向震中逼近的现象;震中附近始终存在地磁总强度、磁偏角、垂直分量的0值线。2)2020~2021年度震中附近各测点时序变化具有高度的一致性,较好地反映出测点附近断裂的协同化活动状态,或许可以作为识别断层进入亚失稳阶段的特征之一。3)分析应力与磁场强度的关系可知,林南断裂中东段、聊城-兰考断裂东北段地磁场总强度增大,地壳应力应处于释放状态;堂邑断裂、林南断裂西段地磁场总强度减小,地壳应力应处于积累状态。前者应力释放对后者的应力积累有促进作用,可能会导致后者的剪应力瞬时增加并超过其强度发生失稳,从而引发平原地震。 展开更多
关键词 平原M_(s)5.5地震 流动地磁 岩石圈磁场异常变化 亚失稳理论 发震机理
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Magnetic Structure of the Earth’s Crust in the White Sea Region
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作者 Lyubov Bakunovich Mikhail Nilov +1 位作者 Nikolay Sharov Boris Belashev 《International Journal of Geosciences》 2021年第11期1007-1020,共14页
The geological structure of the White Sea area and the surrounding land areas has been well studied in the framework of individual case studies. There are a number of local models of the deep structure of the Earth’s... The geological structure of the White Sea area and the surrounding land areas has been well studied in the framework of individual case studies. There are a number of local models of the deep structure of the Earth’s crust available. We propose a uniform assessment of deep crustal bodies responsible for long-period (regional) magnetic anomalies and consider their correlation with surface structures. The aim of the study is to build a three-dimensional magnetic model of the Earth’s crust in the White Sea region using aeromagnetic data and modeling technologies of the Integro software package. The model is formed on the basis of a digital map of the anomalous magnetic field reduced to the pole. The sources of magnetic anomalies are considered to be located in the Earth’s crust. The 3D distribution of the relative magnetic susceptibility of rocks was obtained by solving the inverse problem of <span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">magnetic survey. To separate the magnetic sources by frequency and depth, it was necessary to continue the magnetic field of the model upward and to calculate the TDR derivatives, which determine the lateral boundaries of the sources of positive magnetic field anomalies. 2D distributions of magnetic sources of the model for vertical and horizontal sections with depths of 10, 15 and 20 km are analyzed. The correlation between the surface and deep structures of magnetic sources of the Earth’s crust in the region is shown.</span> 展开更多
关键词 White sea Earth’s Crust Anomalous magnetic field Effective magnetic sus-ceptibility 3D Model
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Electromagnetic Shells of Atoms and the Periodic System of Elements 被引量:2
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作者 Robert A. Sizov 《Journal of Modern Physics》 2016年第16期2374-2397,共24页
Experimental and theoretical researches performed by the author (period: 1969-present) showed that the magnetic spinor particles (magnetic charges) are real structural components of atoms and substance and are immedia... Experimental and theoretical researches performed by the author (period: 1969-present) showed that the magnetic spinor particles (magnetic charges) are real structural components of atoms and substance and are immediate sources of all mag-netic fields and magnetic manifestations in Nature. Magnetic charges, which constitute together with electrical charges the atomic shells, got of the Author’s title: magnetons and antimagnetons (respectively, with magnetic charges g<sup>&minus;</sup> and g<sup>+</sup>, under fundamental condition: g = e). Besides, together with electrons and magnetic charges in the structures of atomic shells, in the same quantities as the electrons, exist real electric antispinors, i.e. the true antielectrons. In the structures of the atomic shells on each electron fitted still three a real spinor particles: two magnetic (magneton and antimagneton) and one electric, i.e. true antielectron with a charge of e<sup>+</sup>. The spinor particles in atomic shells exist in the form of the two spinor associations: the electromagnetic dibispinors or S-Gravitons and magnetic bispinors (spinorial magnetic dipoles). Magnetic bispinors, which inhabited on the 3d and 4f-shells are the sources of the atomic magnetic fields and are responsible at all magnetic manifestations of the so-called magnetic atoms (iron, nickel, cobalt and others). In composition of S-Graviton is two related bispinor (electric and magnetic). S-Gravitons make up bulk of the charged density of atomic shells and are direct sources of the atomic gravitational field.If to replace all electrons on known of the atomic levels and sub-levels on S-Gravitons, can get an idea about the real electromagnetic device atomic shells most of the elements making up the Periodic Table. In article shows features the structural organization real (electromagnetic) shells of atoms that make up the periodic system of elements, as well as is considered the possibility of adaptation of the well-known quantum numbers, the Pauli’s principle and Hund’s rule, in relation to the atomic electromagnetic device. The main reasons for the fact that the real magnetic charges, as well as the true antielectrons, were “buried alive” in the modern theories are as physics confinement them in atoms and substance, which is cardinally different from the confinement, for example, electrons, so and vicious electromagnetic concept of Maxwell. In the framework of this concept really existing in atoms and substance the magnetic charges, have been mistakenly substituted on acts of the mechanical displacement of electrical charges. 展开更多
关键词 magnetic spinor Particles (spinors and Antispinors) magneton and Antimagneton Bispinor Dibispinor s-Graviton Physical Mass Vortex Electromagnetic (Gravitational) field Paragravitation and Ferrogravitation Gravito-Levitation Quantum Numbers
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