Multisatellite observations of the magnetosphere response to changes in the solar wind and interplanetary magnetic field

Abstract. We employ multipoint observations of the magnetosphere to present case and statistical studies of the electromagnetic field and plasma response to interplanetary (IP) shocks. On February 27, 2014 the initial encounter of an IP shock with the magnetopause occurred on the early postnoon magnetosphere, consistent with the observed alignment of the shock with the spiral IMF. The dayside equatorial magnetosphere exhibited a dusk-dawn oscillatory electrical field with a period of ~ 330 s and peak to peak amplitudes of ~ 15 mV/m for a period of 30 min. The intensity of electrons in the energy range from 31.5 to 342 KeV responded with periods corresponding to the shock induced ULF electric field waves. The initial electric field perturbation was directed dawnward for this case study. We then perform a statistical study of Ey variations of the electric field and associated plasma drift Vx and Vy flow velocities for 30 magnetospheric events during the passage of interplanetary shocks. The direction of the initial Vx component of plasma flow is tailward at all local times except the nightside magnetosphere, where flows are sunward near the sun-Earth line but antisunward towards dawn and dusk. The observed directions of the azimuthal velocity Vy predominately agree with those expected for the given spiral or orthospiral shock normal orientation.

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Multisatellite observations of the magnetosphere response to changes in the solar wind and interplanetary magnetic field

Annales Geophysicae ◽

10.5194/angeo-36-1319-2018 ◽

2018 ◽

Vol 36 (5) ◽

pp. 1319-1333 ◽

Cited By ~ 1

Author(s):

Galina Korotova ◽

David Sibeck ◽

Scott Thaller ◽

John Wygant ◽

Harlan Spence ◽

...

Keyword(s):

Solar Wind ◽

Electric Field ◽

Wind Pressure ◽

Local Times ◽

The Sun ◽

Interplanetary Shocks ◽

Ultralow Frequency ◽

Statistical Studies ◽

Solar Wind Pressure ◽

Flow Velocities

Abstract. We employ multipoint observations of the Van Allen Probes, THEMIS, GOES and Cluster to present case and statistical studies of the electromagnetic field, plasma and particle response to interplanetary (IP) shocks observed by the Wind satellite. On 27 February 2014 the initial encounter of an IP shock with the magnetopause occurred on the postnoon magnetosphere, consistent with the observed alignment of the shock with the spiral IMF. The dayside equatorial magnetosphere exhibited a dusk–dawn oscillatory electrical field with a period of ∼330 s and peak-to-peak amplitudes of ∼15 mV m−1 for a period of 30 min. The intensity of electrons in the energy range from 31.5 to 342 KeV responded with periods corresponding to the shock-induced ULF (ultralow frequency) electric field waves. We then perform a statistical study of Ey variations of the electric field and associated plasma drift flow velocities for 60 magnetospheric events during the passage of interplanetary shocks. The Ey perturbations are negative (dusk-to-dawn) in the dayside magnetosphere (followed by positive or oscillatory perturbations) and dominantly positive (dawn-to-dusk direction) in the nightside magnetosphere, particularly near the Sun–Earth line within an L-shell range from 2.5 to 5. The typical observed amplitudes range from 0.2 to 6 mV m−1 but can reach 12 mV during strong magnetic storms. We show that electric field perturbations increase with solar wind pressure, and the changes are especially marked in the dayside magnetosphere. The direction of the Vx component of plasma flow is in agreement with the direction of the Ey component and is antisunward at all local times except the nightside magnetosphere, where it is sunward near the Sun–Earth line. The flow velocities Vx range from 0. 2 to 40 km s−1 and are a factor of 5 to 10 times stronger near noon as they correspond to greater variations of the electric field in this region. We demonstrate that the shock-induced electric field signatures can be classified into four different groups according to the initial Ey electric field response and these signatures are dependent on local time. Negative and bipolar pulses predominate on the dayside while positive pulses occur on the nightside. The ULF electric field pulsations of Pc and Pi types produced by IP shocks are observed at all local times and in the range of periods from several tens of seconds to several minutes. We believe that most electric field pulsations of the Pc5 type in the dayside magnetosphere at L<6 are produced by field line resonances. We show that the direction of the shock normal determines the direction of the propagation of the shock-induced magnetic and plasma disturbances. The observed directions of velocity Vy predominately agree with those expected for the given spiral or orthospiral shock normal orientation.

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Literary Representations of Female Identity

American Journal of Islam and Society ◽

10.35632/ajis.v19i4.1914 ◽

2002 ◽

Vol 19 (4) ◽

pp. 23-41

Author(s):

Safoi Babana-Hampton

Keyword(s):

Electrical Field-Assisted Gene Delivery from Polyelectrolyte Multilayers

Polymers ◽

10.3390/polym12010133 ◽

2020 ◽

Vol 12 (1) ◽

pp. 133

Author(s):

Yu-Che Cheng ◽

Shu-Lin Guo ◽

Kun-Da Chung ◽

Wei-Wen Hu

Keyword(s):

Gene Delivery ◽

Electric Field ◽

Treatment Time ◽

Transfection Efficiency ◽

Polyelectrolyte Multilayers ◽

Aqueous Environment ◽

Layer By Layer ◽

Electrical Field ◽

Lbl Assembly ◽

Electric Field Treatment

To sustain gene delivery and elongate transgene expression, plasmid DNA and cationic nonviral vectors can be deposited through layer-by-layer (LbL) assembly to form polyelectrolyte multilayers (PEMs). Although these macromolecules can be released for transfection purposes, their entanglement only allows partial delivery. Therefore, how to efficiently deliver immobilized genes from PEMs remains a challenge. In this study, we attempt to facilitate their delivery through the pretreatment of the external electrical field. Multilayers of polyethylenimine (PEI) and DNA were deposited onto conductive polypyrrole (PPy), which were placed in an aqueous environment to examine their release after electric field pretreatment. Only the electric field perpendicular to the substrate with constant voltage efficiently promoted the release of PEI and DNA from PEMs, and the higher potential resulted in the more releases which were enhanced with treatment time. The roughness of PEMs also increased after electric field treatment because the electrical field not only caused electrophoresis of polyelectrolytes and but also allowed electrochemical reaction on the PPy electrode. Finally, the released DNA and PEI were used for transfection. Polyplexes were successfully formed after electric field treatment, and the transfection efficiency was also improved, suggesting that this electric field pretreatment effectively assists gene delivery from PEMs and should be beneficial to regenerative medicine application.

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The ABC Concept—Value Added to the Earth Heritage Interpretation?

Geoheritage ◽

10.1007/s12371-021-00558-8 ◽

2021 ◽

Vol 13 (2) ◽

Author(s):

M. Pásková ◽

J. Zelenka ◽

T. Ogasawara ◽

B. Zavala ◽

I. Astete

Keyword(s):

General Education ◽

Value Added ◽

Cultural Aspects ◽

The Earth ◽

Holistic Interpretation ◽

Level Of Knowledge ◽

Internal And External Factors ◽

The Given ◽

Heritage Interpretation

AbstractHolistic interpretation of Earth heritage is one of the most important tasks of UNESCO Global geoparks. The ABC (abiotic, biotic, and cultural interconnections) concept is a potential interpretive approach used in Earth heritage popularization through geotourism. Apart of the deeper understanding of this concept, this study explores the application of this concept in selected geoparks. The Colca and Volcanoes Andagua UNESCO Global Geopark (Peru) and Muroto UNESCO Global Geopark (Japan) served as a case study in the frame of this qualitative research conducted during the summer 2019. Results show that the ABC approach is nearly perfectly understood by both geoparks, however there are both internal and external factors which influence the extent and form of how this concept is applied in practice. Except for specific geographical settings, different stages of geopark product development, and different managerial approaches, they mainly include the level of scientific knowledge and general education in the given geopark, as well as level of knowledge management and networking with another UNESCO global geoparks. The more experienced Muroto Geopark interpretation exhibits a comparatively higher level of visible ABC application, while the Colca and Volcanoes Andagua Geopark can benefit in the future from the natural inclination and ability of the local people to integrate the cultural aspects into their Earth heritage interpretation.

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Context-Aware Adaptation of Component-Based Systems: An Active Repository Approach

Journal of Computer Networks and Communications ◽

10.1155/2012/963728 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Sindolfo Miranda Filho ◽

Julio Melo ◽

Luiz Eduardo Leite ◽

Guido Lemos

Keyword(s):

Context Aware ◽

Current Configuration ◽

Fuzzy Logic Algorithm ◽

Running System ◽

Component Based Software Engineering ◽

Context Aware System ◽

The Given ◽

To Receive ◽

Component Repository

Context-aware systems are able to monitor and automatically adapt their operation accordingly to the execution context in which they are introduced. Component-based software engineering (CBSE) focuses on the development and reuse of self-contained software assets in order to achieve better productivity and quality. In order to store and retrieve components, CBSE employs component repository systems to provide components to the system developers. This paper presents an active component repository that is able to receive the current configuration from the context-aware system and compute the components and the new architecture that better fit the given context. Since the repository has a wide knowledge of available components, it can better decide which configuration is more suitable to the running system. The repository applies Fuzzy logic algorithm to evaluate the adequacy level of the components and GRASP algorithm to mount the new system architecture. In order to verify the feasibility of our approach, we use a digital TV middleware case study to achieve experimental results.

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The roles of vertical advection and eddy diffusion in the equatorial mesospheric semi-annual oscillation (MSAO)

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-7813-2013 ◽

2013 ◽

Vol 13 (15) ◽

pp. 7813-7824 ◽

Cited By ~ 4

Author(s):

R. L. Gattinger ◽

E. Kyrölä ◽

C. D. Boone ◽

W. F. J. Evans ◽

K. A. Walker ◽

...

Keyword(s):

Driving Forces ◽

Eddy Diffusion ◽

Equatorial Region ◽

Local Times ◽

Model Simulations ◽

Vertical Advection ◽

Diffusion Rates ◽

D Model ◽

Vertical Eddy

Abstract. Observations of the mesospheric semi-annual oscillation (MSAO) in the equatorial region have been reported dating back several decades. Seasonal variations in both species densities and airglow emissions are well documented. The extensive observations available offer an excellent case study for comparison with model simulations. A broad range of MSAO measurements is summarised with emphasis on the 80–100 km region. The objective here is not to address directly the complicated driving forces of the MSAO, but rather to employ a combination of observations and model simulations to estimate the limits of some of the underlying dynamical processes. Photochemical model simulations are included for near-equinox and near-solstice conditions, the two times with notable differences in the observed MSAO parameters. Diurnal tides are incorporated in the model to facilitate comparisons of observations made at different local times. The roles of water vapour as the "driver" species and ozone as the "response" species are examined to test for consistency between the model results and observations. The simulations suggest the interactions between vertical eddy diffusion and background vertical advection play a significant role in the MSAO phenomenon. Further, the simulations imply there are rigid limits on vertical advection rates and eddy diffusion rates. For August at the Equator, 90 km altitude, the derived eddy diffusion rate is approximately 1 × 106 cm2 s−1 and the vertical advection is upwards at 0.8 cm s−1. For April the corresponding values are 4 × 105 cm2 s−1 and 0.1 cm s−1. These results from the current 1-D model simulations will need to be verified by a full 3-D simulation. Exactly how vertical advection and eddy diffusion are related to gravity wave momentum as discussed by Dunkerton (1982) three decades ago remains to be addressed.

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Structural, optical and morphology properties of Pt NPs synthesized by laser ablation: case study on effect of electric field

International Nano Letters ◽

10.1007/s40089-021-00364-8 ◽

2022 ◽

Author(s):

Mohammad Bakhtiari ◽

Mohammadreza Hantehzadeh ◽

Elham Darabi

Keyword(s):

Laser Ablation ◽

Electric Field

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The Polymerization of MMA and ST to Prepare Material with Gradient Refractive Index in Electric Field

Advances in Materials Science and Engineering ◽

10.1155/2015/401897 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6

Author(s):

Yao Huang ◽

Daming Wu ◽

Dongyun Ren ◽

Qingyun Meng ◽

Xiaojun Di

Keyword(s):

Molecular Weight ◽

Refractive Index ◽

Electric Field ◽

Cylindrical Sample ◽

Electrical Field ◽

Molecular Weights ◽

The Matrix ◽

Gradient Refractive Index ◽

Scattering Material ◽

Different Parts

Light scattering material with gradient refractive index was prepared under the electrical field by taking methyl methacrylate (MMA) monomer as the matrix with the addition of a little preheated styrene (ST) and peroxidation benzoin formyl (BPO). The material obtained under electrical field presented different transmittance and molecular weight at different parts of the cylindrical sample along the axis of the direction of electric field which led to the layering phenomenon and gradient refractive index. The disparity of molecular weight between different layers can be as much as 230 thousand. There were several peaks in the figure of GPC test of the sample under electric field. This proved that there were polymers with different molecular weights in the sample. Therefore, it can be concluded that electrical field has a significant effect on polymerization.

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DYNAMICS OF THE SEMANTIC COMPLEX OF DOMINANT UNITS IN POETIC TEXT: INTERTEXTUAL ASPECT (a Case Study of L. Cohen’s Poem ‘Elegy’)

Вестник Пермского университета Российская и зарубежная филология ◽

10.17072/2073-6681-2020-4-33-43 ◽

2020 ◽

Vol 12 (4) ◽

pp. 33-43

Author(s):

Ilya V. Sergodeev ◽

Keyword(s):

Contextual Analysis ◽

Personal Pronoun ◽

Greek Mythology ◽

Unit Of Analysis ◽

Christian Culture ◽

Poetic Text ◽

Artistic Images ◽

The Given

The article deals with the dynamics of the semantic complex of dominant units in poetic text. Units of poetic text are divided into constant and dominant ones. Constant units realize the function of the context formation. They have one clear meaning. Dominant units realize the function of semantization. They are poly-interpretative. The methodology of the work is based on the theory of intertextuality which is viewed from the position of structural, interpretative and lingua-cultural approaches. The brief typology and characteristics of intertextual relations are given: auto- (self-quotations, self-allusions), in- (quotations, allusions), para- (structural and compositional units of a text such as a title, an epigraph, etc.) and arch-textuality (genre imitation; referring to well-known artistic images or cultural phenomena). The paper presents the model of analysis of dominant units in poetic text. The analysis is carried out in five steps: fragmentation, contextual analysis, search and determination of intertextual relations between the analyzed unit and units of address texts, contextual analysis of address texts, synthesis of the obtained contextual meanings. The practical material under study is the poem Elegy by the Canadian poet L. Cohen. The unit of analysis is the personal pronoun he in the given poetic text. The paper establishes intertextual relations between Elegy and texts from Greek mythology, the Holy Bible, Christian culture, and other works by L. Cohen. The conducted analysis shows that intertextual relations between the studied units initiate exchange and superimposition of their context meanings. As a result, the studied unit can have several meanings (some of which are not present in dictionaries but unique for the given author) within the same context. In this way, the dynamics of the semantic complex of the studied units and poetic text is realized.

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Experiential Learning in Action: A Collaborative Inquiry

The Qualitative Report ◽

10.46743/2160-3715/2017.2551 ◽

2017 ◽

Author(s):

Alexios Brailas ◽

Stella-Maria Avani ◽

Christina Gkini ◽

Maria-Afroditi Deilogkou ◽

Konstantinos Koskinas ◽

...

Keyword(s):

Experiential Learning ◽

Paradigm Shift ◽

Research Method ◽

Course Design ◽

Research Approach ◽

Thick Description ◽

Practice Activity ◽

The Given ◽

Reflection On Practice

In this paper, we describe a case study of an undergraduate course on research methodology, in which lecture was reduced to a minimum and replaced with experiential learning activities. The course design was project-based and spiraled through four phases: a mini-lecture on a given research method, an “early practice” activity, and “reflection on practice” tutor-guided small group collaborations which led to deeper understanding of the given research method. This particular course design constitutes a paradigm shift in comparison to the predominant in Greek higher education didactic pedagogical model. How this paradigm shift was received and experienced by the participating students? In order to get rich insights into the lived experiences of the participants (N=15), we adopted a blended qualitative research approach: thematic analysis combined with students’ critical reflections on their experience, aiming to produce a thick description of our intervention. The course design and implementation positioned students and their tutors as knowledgeable actors able to contribute research insights through their transactions.

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