Imaging sunspots using helioseismic methods

2005 ◽  
Vol 363 (1837) ◽  
pp. 2761-2775 ◽  
Author(s):  
C.H Tong
Keyword(s):  
Seismic Imaging ◽  
Structural Characteristics ◽  
Imaging Techniques ◽  
Solar Physics ◽  
Interdisciplinary Approach ◽  
Active Regions ◽  
Solar Interior ◽  
Seismic Methods ◽  
New Research ◽  
First Time

The origin of sunspots is one of the most fundamental and yet poorly understood areas in solar physics. Imaging local anomalous features in the solar interior offers a direct way to unravel the underlying physical processes of sunspots and the mechanisms behind their formation. The advent of local helioseismology in the last few years has, for the first time, made it possible to image local internal solar structures. High-resolution satellite and ground telescope data which reveal the details of the vibrations of the visible solar surface are essential in the development of local helioseismology. We are now in a position to transfer the seismic methods that have traditionally been used to study the Earth's interior to solar investigations. This interdisciplinary approach to developing seismic imaging techniques is opening up new ways of understanding the flow and other structural characteristics beneath sunspots. In this article, I review recent progress in the imaging of sunspots and the surrounding solar active regions. By highlighting the strengths of seismic methods and the challenges facing local helioseismology, I discuss some of the new research directions and possibilities that have arisen from this novel type of seismic imaging.

scholarly journals The formation of a penumbra as observed with the German VTT and SoHO/MDI

2010 ◽  
Vol 6 (S273) ◽  
pp. 134-140 ◽  
Author(s):  
Rolf Schlichenmaier ◽  
Nazaret Bello González ◽  
Reza Rezaei
Keyword(s):  
Magnetic Flux ◽  
Solar Physics ◽  
Active Regions ◽  
Solar Interior ◽  
Doppler Velocity ◽  
Solar Photosphere ◽  
Multi Wavelength ◽  
2D Imaging ◽  
The Magnetic Field ◽  
Field Inclination

AbstractThe generation of magnetic flux in the solar interior and its transport to the outer solar atmosphere will be in the focus of solar physics research for the next decades. One key-ingredient is the process of magnetic flux emergence into the solar photosphere, and the reorganization to form the magnetic phenomena of active regions like sunspots and pores.On July 4, 2009, we observed a region of emerging magnetic flux, in which a proto-spot without penumbra forms a penumbra within some 4.5 hours. This process is documented by multi-wavelength observations at the German VTT: (a) imaging, (b) data with high resolution and temporal cadence acquired in Fe I 617.3 nm with the 2D imaging spectropolarimter GFPI, and (c) scans with the slit based spectropolarimeter TIP in Fe I 1089.6 nm. MDI contiuum maps and magnetograms are used to follow the formation of the proto-spot, and the subsequent evolution of the entire active region.During the formation of the penumbra, the area and the magnetic flux of the spot increases. The additional magnetic flux is supplied by the adjacent region of emerging magnetic flux: As emerging bipole separate, the poles of the spot polarity migrate towards the spot, and finally merge with it. As more and more flux is accumulated, a penumbra forms. From inversions we infer maps for the magnetic field and the Doppler velocity (being constant along the line-of-sight). We calculate the magnetic flux of the forming spot and of the bipole footpoints that merge with the proto-spot. We witness the onset of the Evershed flow and the associated enhance of the field inclination as individual penumbral filaments form. Prior to the formation of individual penumbral sectors we detect the existence of ‘counter’ Evershed flows. These in-flows turn into the classical radial Evershed outflows as stable penumbra segments form.

Collections of Memory Institutions: New Trends for Research

2012 ◽  
Vol 2 ◽  
pp. 9-18
Author(s):  
Arvydas Pacevičius
Keyword(s):  
Cultural Theory ◽  
Interdisciplinary Approach ◽  
Frame Of Reference ◽  
The Other ◽  
Systematic Research ◽  
Library History ◽  
Modern Library ◽  
Research Paradigms ◽  
Theoretical Perspectives ◽  
New Research

The publication features information on research done during the Bibliotheca Lituana project. In particular the focus is on collections of memory institutions, new perspectives on library and other memory institution, i.e. archives, museums, research. Modern library history has adopted relevant theoretical perspectives from social and cultural theory. Currently these perspectives incorporate not only the activities and collections of the aforementioned institutions but also the more widely interpreted information infrastructure, that do not have libraries as their main frame of reference. Problems faced publishing archival sources are also examined. It was determined that insufficient attention is given to research and publication of old catalogues, inventories and book listings. On the other hand a unified system and methodology for publishing of the aforementioned sources does not exist. We come to a conclusion that through new research paradigms, an interdisciplinary approach and change of thought in the archival, librarian and museology communities, we can start systematic research of libraries and other memory institutions. Their results would complement the pages of the continued Bibliotheca Lituana publications.

scholarly journals Structure-Properties Correlation of Cross-Linked Penicillin G Acylase Crystals

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 451
Author(s):  
Marta Kubiak ◽  
Janine Mayer ◽  
Ingo Kampen ◽  
Carsten Schilde ◽  
Rebekka Biedendieck
Keyword(s):  
Mechanical Stability ◽  
Structural Characteristics ◽  
Penicillin G ◽  
Bacillus Species ◽  
Diffusion Limitations ◽  
Small Water ◽  
Long Term Stability ◽  
Atomic Force ◽  
First Time

In biocatalytic processes, the use of free enzymes is often limited due to the lack of long-term stability and reusability. To counteract this, enzymes can be crystallized and then immobilized, generating cross-linked enzyme crystals (CLECs). As mechanical stability and activity of CLECs are crucial, different penicillin G acylases (PGAs) from Gram-positive organisms have proven to be promising candidates for industrial production of new semisynthetic antibiotics, which can be crystallized and cross-linked to characterize the resulting CLECs regarding their mechanical and catalytic properties. The greatest hardness and Young’s modulus determined by indentation with an atomic force microscope were observed for CLECs of Bacillus species FJAT-PGA CLECs (26 MPa/1450 MPa), followed by BmPGA (Priestia megaterium PGA, 23 MPa/1170 MPa) and BtPGA CLECs (Bacillus thermotolerans PGA, 11 MPa/614 MPa). In addition, FJAT- and BtPGA CLECs showed up to 20-fold higher volumetric activities compared to BmPGA CLECs. Correlation to structural characteristics indicated that a high solvent content and low number of cross-linking residues might lead to reduced stability. Furthermore, activity seems to be restricted by small water channels due to severe diffusion limitations. To the best of our knowledge, we show for the first time in this study that the entire process chain for the characterization of diverse industrially relevant enzymes can be performed at the microliter scale to discover the most important relationships and limitations.

Vietnamese Proverbs From a Cultural Perspective

2019 ◽  
Author(s):  
Thanh Quy Ngo Thi ◽  
◽  
Hong Minh Nguyen Thi ◽  
Keyword(s):  
Cultural Values ◽  
Language Use ◽  
Interdisciplinary Approach ◽  
Research Direction ◽  
Point Of View ◽  
Traditional Values ◽  
Cultural Perspective ◽  
Language And Culture ◽  
Speakers Of Other Languages ◽  
New Research

Proverbs are important data depicting the traditional culture of each nation. Vietnamese proverbs, dated thousands of years ago, are an immense valuable treasure of experience which the Vietnamese people desire to pass to the younger generations. This paper aims to explore the unique and diversified world of intelligence and spirits of the Vietnamese through a condensed and special literary genre, as well as a traditional value of the nation (Nguyen Xuan Kinh 2013, Tran Ngoc Them 1996, Le Chi Que and Ngo Thi Thanh Quy 2014). Through an interdisciplinary approach, from an anthropological point of view, approaching proverbs we will open up a vast treasure of knowledge and culture of all Vietnamese generations. The study has examined over 16,000 Vietnamese proverbs and analysed three groups expressing Vietnamese people’s behaviors toward nature, society and their selves, and compared them with English and Japanese proverbs. The research has attempted to explore the beauty of Vietnamese language, cultural values and the souls and personalities of Vietnam. Approaching Vietnamese proverbs under the interdisciplinary perspective of language, culture and literature is a new research direction in the field of Social Sciences and Humanity in Vietnam. From these viewpoints, it is seen that proverbs have remarkably contributed to the language and culture of Vietnam as well as and constructed to the practice of language use in everyday life which is imaginary, meaningful and effective in communication. Furthermore, the study seeks to inspire the Vietnamese youth’s pride in national identity and to encourage their preservation and promotion for traditional values of the nation in the context of integration and globalisation. In the meantime, it would be favourable to introduce and market the beauty of Vietnamese language, culture and people to the world, encouraging the speakers of other languages to study, explore and understand Vietnam.

Physical properties and seismic imaging of massive sulfides

Geophysics ◽  
2000 ◽  
Vol 65 (6) ◽  
pp. 1882-1889 ◽  
Author(s):  
Matthew H. Salisbury ◽  
Bernd Milkereit ◽  
Graham Ascough ◽  
Robin Adair ◽  
Larry Matthews ◽  
...  
Keyword(s):  
Physical Properties ◽  
Seismic Imaging ◽  
Country Rock ◽  
Imaging Techniques ◽  
Geometric Constraints ◽  
Eastern Canada ◽  
Massive Sulfides ◽  
Ore Bodies ◽  
Text Density ◽  
Representative Samples

Laboratory studies show that the acoustic impedances of massive sulfides can be predicted from the physical properties ([Formula: see text], density) and modal abundances of common sulfide minerals using simple mixing relations. Most sulfides have significantly higher impedances than silicate rocks, implying that seismic reflection techniques can be used directly for base metals exploration, provided the deposits meet the geometric constraints required for detection. To test this concept, a series of 1-, 2-, and 3-D seismic experiments were conducted to image known ore bodies in central and eastern Canada. In one recent test, conducted at the Halfmile Lake copper‐nickel deposit in the Bathurst camp, laboratory measurements on representative samples of ore and country rock demonstrated that the ores should make strong reflectors at the site, while velocity and density logging confirmed that these reflectors should persist at formation scales. These predictions have been confirmed by the detection of strong reflections from the deposit using vertical seismic profiling and 2-D multichannel seismic imaging techniques.

Comparison of Some Seismic Imaging Techniques

1980 ◽  
pp. 737-760
Author(s):  
Thomas T. Hu ◽  
Keith Wang ◽  
Fred Hilterman
Keyword(s):  
Seismic Imaging ◽  
Imaging Techniques

First Results from the VULCAN Diffractometer at the SNS

2010 ◽  
Vol 652 ◽  
pp. 105-110 ◽  
Author(s):  
X.L. Wang ◽  
Thomas Holden ◽  
A.D. Stoica ◽  
K. An ◽  
H.D. Skorpenske ◽  
...  
Keyword(s):  
Neutron Beam ◽  
Research Opportunities ◽  
Instrument Performance ◽  
Measurement Results ◽  
First Results ◽  
Design Calculations ◽  
New Research ◽  
First Time

On Friday June 26, 2009, the neutron beam shutter for the VULCAN diffractometer at the SNS was opened for the first time. Initial measurements to characterize the instrument performance are reported. It is shown that the measurement results are by and large in agreement with design calculations. New research opportunities with VULCAN are discussed.

scholarly journals CULTURE-BASED STUDIES’ TOPOGRAPHY IN THE MODERN FRENCH SOCIAL SCIENCE

2019 ◽  
pp. 14-17
Author(s):  
B. E. Nosenok
Keyword(s):  
Social Sciences ◽  
Cultural Studies ◽  
Cultural History ◽  
Interdisciplinary Approach ◽  
The Body ◽  
Social Knowledge ◽  
History Of Culture ◽  
Critical Turn ◽  
Definition Of ◽  
First Time

Cultural studies as a humanities researcher takes the place of an expert. The relevance of this topic is due to the lack of development of the issues of “culture-based studies” in Ukrainian culturology. There is a lack of translated into French or Ukrainian languages of French sources published since 1975. French culturological science, which developed after 1975, is almost not represented in Ukrainian culturology. The present stage of the development of French historiography, which lies at the heart of cultural history, and cultural studies, is associated with increased attention to social knowledge. This stage is characterized by the deployment of a “critical turn”, which proceeds from the following principles: the interdisciplinary approach, the significance of cultural expertise, the severity of publications and the multiplicity of their forms, multidisciplinarity. The “critical turn” affects the following spheres of knowledge: la Culturologie, les Études culturelles, les Sciences de la Culture. The article substantiates the relevance of the use of the concept of “culture-based studies” to the definition of processes that are unfolding within the framework of French humanities and are associated exclusively with the theoretical formations in the context of the social sciences. The purpose of the article is to outline a map of culture-based studies in the field of French humanitaristics. The methodology of the article is based on the application of interdisciplinary and multidisciplinary approaches to research in the field of culturology. Also, methodological developments in the field of “critical turn” and the achievements of the sociological circle and the interdisciplinary discussion club “Eranos” were applied. The scientific novelty of the article is to substantiate the appropriateness of the use of the concept of “culture-based studies” on the definition of processes that are unfolding within the framework of French humanitaristics and relate exclusively to theoretical formations in the context of social sciences. This concept to the field of Ukrainian culturology is introduced for the first time. Also, for the first time, the place and forms of culturology in French humanities were clarified. Conclusions. Working with a source base and methodology is one of the points that are compulsory on the way to the solution of the tasks, the main of which is the formation of the body of fundamental works for French history (including the history of culture) and historiography of the period since 1975 year to the present day. On the basis of this building, there is the prospect of building an alternative national cultural history project addressed to the vector of the French historiographical, historical-anthropological and cultural-related issues in the field of social knowledge. The article presents the arguments why it is appropriate to use the concept of “culture-based studies” in the context of conducting research in relation to French humanitaristics, in particular, the modern period of its development.

scholarly journals Extraction, Structural Characterization, and Anti-Hepatocellular Carcinoma Activity of Polysaccharides From Panax ginseng Meyer

2021 ◽  
Vol 11 ◽  
Author(s):  
Hui Jia ◽  
Bin Zhao ◽  
Fangfang Zhang ◽  
Ramesh Kumar Santhanam ◽  
Xinying Wang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Hepg2 Cells ◽  
Cytotoxic Effect ◽  
Structural Characteristics ◽  
Gel Permeation Chromatography ◽  
Salting Out ◽  
Gel Permeation ◽  
Acidic Polysaccharides ◽  
Hepg2 Cell Lines ◽  
First Time

Polysaccharides are the main active ingredients of ginseng. To extract the most effective polysaccharides against hepatocellular carcinoma (HCC), we isolated and characterized the polysaccharides from the mountain cultivated ginseng (MCG) and compared their composition and cytotoxic effect with cultivated ginseng (CG) polysaccharide against HepG2 cell lines for the first time. MCG polysaccharides and CG polysaccharides were fractionated into two fractions such as MTPS-1, MTPS-2 and CTPS-1, CTPS-2 by salting out, respectively. Compared to CG, MCG possessed appreciable cytotoxic effect against HepG2 cells among that MTPS-1 possess fortified effect. Then, MTPS-1 was selected for further isolation process and seven acidic polysaccharides (MCGP-1–MCGP-7) were obtained using ethanol precipitation, ion-exchange, and gel permeation chromatography techniques. Structural characteristics of the polysaccharides (MCGP-1–MCGP-7) were done by adapting methylation/GC-MS and NMR analysis. Overall, MCGP-3 polysaccharide was found to possess significant cytotoxic effect against HepG2 cells with the IC50 value.

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