Zebra pattern flux density observation during the type IV burst on October 12, 1981

In the first four years of operation with the 80 MHz heliograph at Culgoora, 24 events classified as moving type IV were observed. Their observed characteristics can be interpreted in terms of gyro-synchrotron radiation from mildly relativistic electrons. Many of these events have been presented at previous ASA meetings and 12 have been discussed in the literature in detail.

Download Full-text

The Effectiveness of E-CALLISTO System in Predicting Geomagnetic Disturbance

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d9448.079220 ◽

2020 ◽

Vol 9 (2) ◽

pp. 699-702

Keyword(s):

Solar Radio ◽

Solar Maximum ◽

Geomagnetic Disturbance ◽

Global Network ◽

Frequency Range ◽

Zebra Pattern ◽

Type Iv ◽

Radio Signals ◽

Solar Storm ◽

Fine Structures

This study focuses on analyzation of solar radio burst (SRB) data obtained by e-CALLISTO system in order to predict the occurrence of geomagnetic storm. E-CALLISTO is a global network of solar spectrometer that continually generates the observed radio signals in a form of spectrographs. Previous studies have strongly proved that the source of geomagnetic disturbance turned out to be type IV SRB which can be detected by CALLISTO instrument. Therefore, we selected 4 stations located at different locations to study the effectiveness and consistency of this system in detecting type IV bursts associated to solar storm during solar maximum. The data chosen was on 10th September 2014 where type IV bursts were formed at 1727 UT until 1745 UT within a frequency range of 135MHz to 390MHz. Accompanying the bursts was a halo CME prior to the bursts’ formation and an X1.6 flare was registered. From the results obtained by all stations, the pattern of the bursts depicts the same characteristic as theory says, by which, they emit a broadband continuum in a zebra pattern with varying fine structures. The formation of the bursts is due to magnetic reconnection and disruption of magnetic loops during large flares on Sept. 10th. As a consequence to type IV bursts associated to a vigorous CME, a major G2 storm was reported by NOAA a couple of days later. The presented results have shown a parallel correlation between type IV bursts detected by those 4 stations and the commencement of geomagnetic disturbance which took place 2 days afterwards.

Download Full-text

The LDE-Type Flare Occurrence (1969-1993)

International Astronomical Union Colloquium ◽

10.1017/s0252921100025458 ◽

1994 ◽

Vol 144 ◽

pp. 279-282

Author(s):

A. Antalová

Keyword(s):

Time Series ◽

Fourier Analysis ◽

Sunspot Cycle ◽

List Type ◽

Type Number ◽

Solar Cycles ◽

Type Iv ◽

Long Duration ◽

Cycle Maximum ◽

Flare Index

AbstractThe occurrence of LDE-type flares in the last three cycles has been investigated. The Fourier analysis spectrum was calculated for the time series of the LDE-type flare occurrence during the 20-th, the 21-st and the rising part of the 22-nd cycle. LDE-type flares (Long Duration Events in SXR) are associated with the interplanetary protons (SEP and STIP as well), energized coronal archs and radio type IV emission. Generally, in all the cycles considered, LDE-type flares mainly originated during a 6-year interval of the respective cycle (2 years before and 4 years after the sunspot cycle maximum). The following significant periodicities were found:• in the 20-th cycle: 1.4, 2.1, 2.9, 4.0, 10.7 and 54.2 of month,• in the 21-st cycle: 1.2, 1.6, 2.8, 4.9, 7.8 and 44.5 of month,• in the 22-nd cycle, till March 1992: 1.4, 1.8, 2.4, 7.2, 8.7, 11.8 and 29.1 of month,• in all interval (1969-1992):a)the longer periodicities: 232.1, 121.1 (the dominant at 10.1 of year), 80.7, 61.9 and 25.6 of month,b)the shorter periodicities: 4.7, 5.0, 6.8, 7.9, 9.1, 15.8 and 20.4 of month.Fourier analysis of the LDE-type flare index (FI) yields significant peaks at 2.3 - 2.9 months and 4.2 - 4.9 months. These short periodicities correspond remarkably in the all three last solar cycles. The larger periodicities are different in respective cycles.

Download Full-text

Labelling of non-A, non-B hepatitis infected chimpanzee hepatocytes with nuclease-gold conjugates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111367 ◽

1984 ◽

Vol 42 ◽

pp. 250-251

Author(s):

G. D. Gagne ◽

M. F. Miller ◽

D. A. Peterson

Keyword(s):

Endoplasmic Reticulum ◽

Experimental Infection ◽

Uranyl Acetate ◽

Type I ◽

Cellular Injury ◽

Type Ii ◽

Tubular Structures ◽

Type Iii ◽

Type Iv ◽

Infected Chimpanzee

Experimental infection of chimpanzees with non-A, non-B hepatitis (NANB) or with delta agent hepatitis results in the appearance of characteristic cytoplasmic alterations in the hepatocytes. These alterations include spongelike inclusions (Type I), attached convoluted membranes (Type II), tubular structures (Type III), and microtubular aggregates (Type IV) (Fig. 1). Type I, II and III structures are, by association, believed to be derived from endoplasmic reticulum and may be morphogenetically related. Type IV structures are generally observed free in the cytoplasm but sometimes in the vicinity of type III structures. It is not known whether these structures are somehow involved in the replication and/or assembly of the putative NANB virus or whether they are simply nonspecific responses to cellular injury. When treated with uranyl acetate, type I, II and III structures stain intensely as if they might contain nucleic acids. If these structures do correspond to intermediates in the replication of a virus, one might expect them to contain DNA or RNA and the present study was undertaken to explore this possibility.

Download Full-text

Effects of EDTA, Hyaluronidase and Collagenase on Epiphyseal Cartilage Matrix

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100020 ◽

1968 ◽

Vol 26 ◽

pp. 56-57

Author(s):

H. Clarke Anderson ◽

Priscilla R. Coulter

Keyword(s):

Light And Electron Microscopy ◽

Matrix Vesicles ◽

Cartilage Matrix ◽

Collagen Fibrils ◽

Epiphyseal Cartilage ◽

Dense Matrix ◽

Type Iv ◽

Bovine Testicular Hyaluronidase ◽

The Matrix ◽

Testicular Hyaluronidase

Epiphyseal cartilage matrix contains fibrils and particles of at least 5 different types: 1. Banded collagen fibrils, present throughout the matrix, but not seen in the lacunae. 2. Non-periodic fine fibrils <100Å in diameter (Fig. 1), which are most notable in the lacunae, and may represent immature collagen. 3. Electron dense matrix granules (Fig. 1) which are often attached to fine fibrils and collagen fibrils, and probably contain protein-polysaccharide although the possibility of a mineral content has not been excluded. 4. Matrix vesicles (Fig. 2) which show a selective distribution throughout the epiphysis, and may play a role in calcification. 5. Needle-like apatite crystals (Fig. 2).Blocks of formalin-fixed epiphysis from weanling mice were digested with the following agents in 0.1M phosphate buffer: a) 5% ethylenediaminetetraacetate (EDTA) at pH 8.3, b) 0.015% bovine testicular hyaluronidase (Sigma, type IV, 750 units/mg) at pH 5.5, and c) 0.1% collagenase (Worthington, chromatograhically pure, 200 units/mg) at pH 7.4. All digestions were carried out at 37°C overnight. Following digestion tissues were examined by light and electron microscopy to determine changes in the various fibrils and particles of the matrix.

Download Full-text

Field Distribution of Strongly Excited Magnetic Lenses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114323 ◽

1975 ◽

Vol 33 ◽

pp. 140-141

Author(s):

M. Strojnik

Keyword(s):

Flux Density ◽

Field Distribution ◽

Optical Axis ◽

Operating Point ◽

Pole Piece ◽

Partial Saturation ◽

Axial Flux ◽

The Stability

Magnetic lenses operating in partial saturation offer two advantages in HVEM: they exhibit small cs and cc and their power depends little on the excitation IN. Curve H, Fig. 1, shows that the maximal axial flux density Bz max of one of the lenses investigated changes between points (3) and (4) by 5% as the excitation varies by 40%. Consequently, the designer can relax the requirements concerning the stability of the lens current supplies. Saturated lenses, however, can only be used if (i) unwanted fields along the optical axis can be controlled, (ii) 'wobbling' of the optical axis due to inhomogeneous saturation around the pole piece faces is prevented, (iii) ample ampere-turns can be squeezed into the space available, and (iv) the lens operating point covers a sufficient range of accelerating voltages.

Download Full-text

Fine Structure of Type IV Glycogenosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098812 ◽

1981 ◽

Vol 39 ◽

pp. 464-465

Author(s):

P.K. Simons

Keyword(s):

Needle Biopsy ◽

Tissue Concentration ◽

Inborn Errors ◽

Rare Type ◽

Type Iv ◽

Iron Copper ◽

Proper Diagnosis ◽

Type Iv Glycogenosis ◽

Loss Of Appetite ◽

Enzymatic Defect

Glycogenosis is defined as any condition in which the tissue concentration of glycogen is increased. There are currently ten recognized variants of glycogenosis that are heritable inborn errors of metabolism. The specific enzymatic defect in each of the variants is known or at least suspected. In all cases, the enzymatic defect prevents the proper metabolism or formation of the glycogen molecule. The clinical and histologic differences between the types of glycogenosis is important to a proper diagnosis after the presence of such a condition is realized. This study was initiated to examine the ultrastructure of the rare Type IV Glycogenosis (Amylopectinosis) of which there is very little morphologic characterization in the literature.Liver tissue was obtained by needle biopsy from a 12-month-old Oriental female who was originally admitted to the hospital after observation of poor development, loss of appetite, and hepatomegaly. The majority of the tissue was fixed for light microscopy in neutral buffered formalin and processed using routine and special staining procedures (reticulin, trichrome, iron, copper, PAS, PAS-diastase and PAS-pectinase.

Download Full-text

Biodegradable polyester neuroprostheses promote the reconnection of separated peripheral nerve stubs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130109 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1094-1095

Author(s):

Beverly L. Giammara ◽

Jennifer S. Stevenson ◽

Peggy E. Yates ◽

Robert H. Gunderson ◽

Jacob S. Hanker

Keyword(s):

Image Analysis ◽

Basement Membrane ◽

Periodic Acid ◽

Light And Electron Microscopy ◽

Computer Assisted ◽

Type Iii Collagen ◽

Image Analysis System ◽

Biodegradable Polyester ◽

Adult Rats ◽

Type Iv

An 11mm length of sciatic nerve was removed from 10 anesthetized adult rats and replaced by a biodegradable polyester Vicryl™ mesh sleeve which was then injected with the basement membrane gel, Matrigel™. It was noted that leg sensation and movement were much improved after 30 to 45 days and upon sacrifice nerve reconnection was noted in all animals. Epoxy sections of the repaired nerves were compared with those of the excised segments by the use of a variation of the PAS reaction, the PATS reaction, developed in our laboratories for light and electron microscopy. This microwave-accelerated technique employs periodic acid, thiocarbohydrazide and silver methenamine. It stains basement membrane or Type IV collagen brown and type III collagen (reticulin), axons, Schwann cells, endoneurium and perineurium black. Epoxy sections of repaired and excised nerves were also compared by toluidine blue (tb) staining. Comparison of the sections of control and repaired nerves was done by computer-assisted microscopic image analysis using an Olympus CUE-2 Image Analysis System.

Download Full-text