scholarly journals The solar—stellar connection: the relationship between flaring rates, flare power and quiescent X-ray background

1989 ◽  
Vol 104 (2) ◽  
pp. 13-16
Author(s):  
Richard A. Harrison ◽  
Gillian Pearce ◽  
Andrew Skumanich
Keyword(s):  
Power Loss ◽  
Inverse Relationship ◽  
Emission Lines ◽  
Flare Activity ◽  
X Ray ◽  
Band Power ◽  
Red Dwarfs ◽  
The Subject ◽  
X Ray Background ◽  
The Relationship

The nature of flare activity on dMc stars (red dwarfs with strong chromospheric IIα emission lines) has been the subject of many studies. Some years ago Lacy et al. (1976) demonstrated a relationship (see also Doyle et al., 1986) between mean flare power and quiescent luminosity, in the photometric U-band. This study was extended, independently, by Skumanich (1985, 1986) and Doyle and Butler (1985) to show that the time averaged U-band power-loss due to flaring is linearly related to a star's quiescent X-ray luminosity. Skumanich also showed an inverse relationship between a star's flaring-rate and its quiescent X-ray luminosity.

scholarly journals Evolution and State of the Local ISM

1996 ◽  
Vol 171 ◽  
pp. 442-442
Author(s):  
T. Schmutzler ◽  
D. Breitschwerdt
Keyword(s):  
Basic Feature ◽  
Emission Lines ◽  
Continuum Emission ◽  
Ionization Equilibrium ◽  
X Ray ◽  
Self Consistent ◽  
X Ray Background ◽  
Collisional Ionization ◽  
Consistent Approach ◽  
The Continuum

The most puzzling observations concerning the LISM (distance < 100 pc) can be explained by a fast adiabatically cooled gas in the cavity of an old superbubble. The ultrasoft X-ray background and contributions to the C- and M-bands are due to the continuum emission of delayed recombination [1]. In contrast to collisional ionization equilibrium (CIE) models, but consistent with recent observations [2], our model predicts a lack of emission lines and a low emissivity in the EUV range. In the figure below we compare the emissivities resulting from CIE at T = 106 K and those from our model at T = 4.2 × 104 K. The basic feature of our model is a thermally self-consistent approach of the time-dependent evolution.

scholarly journals The Soft X-ray Background Spectrum from DXS

1997 ◽  
Vol 166 ◽  
pp. 83-90 ◽  
Author(s):  
W.T. Sanders ◽  
R.J. Edgar ◽  
D.A. Liedahl ◽  
J.P. Morgenthaler
Keyword(s):  
Galactic Plane ◽  
Emission Lines ◽  
Background Spectrum ◽  
Local Bubble ◽  
X Ray ◽  
Hot Plasma ◽  
Solar Abundances ◽  
Ionic Emission ◽  
X Ray Background ◽  
Ionization Balance

AbstractThe Diffuse X-ray Spectrometer (DXS) obtained spectra of the low energy X-ray (44 – 83 Å) diffuse background near the galactic plane from galactic longitudes 150° ≲ l ≲ 300° with ≲ 3 Å spectral resolution and ~ 15° angular resolution. Thus, DXS measured X-ray spectra that arise almost entirely from within the Local Bubble. The DXS spectra show emission lines and emission-line blends, indicating that the source of the X-ray emission is thermal – hot plasma in the Local Bubble. The measured spectra are not consistent with those predicted by standard coronal models, either with solar abundances or depleted abundances, over the temperature range 105 – 107 K. The measured spectra are also inconsistent with the predictions of various non-equilibrium models. A nearly acceptable fit to DXS spectra can be achieved using a hybrid model that combines the Raymond & Smith ionization balance calculation with recently calculated (by DAL) ionic emission lines.

scholarly journals Features in the Soft X-ray Background

1990 ◽  
Vol 115 ◽  
pp. 146-155
Author(s):  
R. Rothenflug
Keyword(s):  
Energy Resolution ◽  
Line Emission ◽  
Spatial Variations ◽  
Emission Lines ◽  
X Ray ◽  
Hot Gas ◽  
The North ◽  
North Polar ◽  
X Ray Background ◽  
Japanese Group

AbstractThe soft X-ray background is explained in terms of emission coming from hot gas. Most of these soft X-ray data were obtained by proportional counters with a poor energy resolution. Instruments having the capability to resolve lines were only flown by two groups: a GSPC by a Japanese group and a SSD by a french-american collaboration. They both detected the 0 VII line emission coming from the soft X-ray background and so proved the thermal nature of the emission. The implications of these results on possible models for the local hot medium will be discussed. The same detectors observed part of the North Polar Spur. They detected emission lines coming from different species (0 VII,Fe XVII,Ne IX). Spatial variations of line ratios for this object could be due to non-equilibrium ionization effects.

scholarly journals PREVALENCE OF PERIAPICAL TISSUE DISEASES

2021 ◽  
Vol 17 (2) ◽  
pp. 38-42
Author(s):  
Kira Betkova ◽  
Larisa Lomiashvili ◽  
Anna Chekina ◽  
Irina Poselyanova
Keyword(s):  
Inverse Relationship ◽  
Endodontic Treatment ◽  
Average Level ◽  
Low Level ◽  
Clinical Observations ◽  
Caries Treatment ◽  
Medical Documents ◽  
The Subject ◽  
The Difference ◽  
The Relationship

The epidemiological aspects of endodontics in comparison with the epidemiology of caries have been insufficiently studied, especially in our country. Aim. The purpose of this work is to assess the endodontic status of patients depending on the level of dental caries resistance. Material and methods. We, based on clinical observations, put forward an assumption about the relationship between the frequency and nature of complications of caries and the level of their resistance to disease according to Nedosenko V.B. The subject of our study was to test this assumption on factual material. The materials of the study were medical documents of 292 patients treated for diseases of the periapical tissues. Orthopantomograms of these patients were analyzed. Methods of statistical analysis were used for assessments and conclusions: Kullback's information statistics and the difference method. Results. When considering the relationship between complications of caries and levels of resistance, an inverse relationship was found, that is, among persons with an average level of dental resistance to caries, the frequency of complicated forms is much lower than among persons with low and very low (p < 0.001). Most often, diseases of the periapical tissues with a destructive process in the periodontium occurred in persons with a low level of resistance. The frequency of diagnostics of destructive periodontitis arising without endodontic treatment and periodontitis arising after endodontic treatment in patients with an average level of resistance is lower than in patients with a low level of resistance. Discussions. The lower the level of resistance of teeth to caries, the more often untreated periodontitis is detected, more often destructive periodontitis occurs as an outcome of endodontic treatment for pulpitis. Conclusions. The data we have obtained allow us to increase the effectiveness of caries treatment, taking into account the level of tooth resistance.

The solar-stellar connection - The relationship between flaring rates, flare power, and quiescent X-ray background

1988 ◽  
Vol 332 ◽  
pp. 1058 ◽  
Author(s):  
Richard A. Harrison ◽  
Gillian Pearce ◽  
Andrew Skumanich
Keyword(s):  
X Ray ◽  
X Ray Background ◽  
The Relationship

scholarly journals Stellar Flare Statistics - Physical Consequences

1989 ◽  
Vol 104 (1) ◽  
pp. 375-386
Author(s):  
N. I. Shakhovskaya
Keyword(s):  
Observational Data ◽  
Decay Rates ◽  
Emission Lines ◽  
Flare Activity ◽  
Total Radiation ◽  
Stellar Flare ◽  
X Ray ◽  
Statistical Correlations ◽  
Physical Consequences

AbstractThe observational data permit us to establish clear statistical correlations between different parameters of stellar flare activity and the characteristics of quiet stars. These relations are: (i)between energies and frequencies of flares on stars of different luminosities;(ii)between total radiation energies of flares and quiet stars both in X-ray and Balmer emission lines;(iii)between flare decay rates just after the maxima and flare luminosities at maxima.

scholarly journals The Interrelation of Perceived and Unconscious Reactions in the Situation of the Rank Assessment of Preferences Among Several Alternatives

2020 ◽  
Vol 13 (4) ◽  
pp. 25-35
Author(s):  
B.G. Meshcheryakov ◽  
A.I. Nazarov ◽  
N.V. Rychagova ◽  
S.N. Rychagov
Keyword(s):  
Emotional Response ◽  
Inverse Relationship ◽  
Movement Trajectory ◽  
The Unconscious ◽  
Final Choice ◽  
Subjective Assessments ◽  
Conscious Choice ◽  
Skin Response ◽  
The Subject ◽  
The Relationship

A pilot experiment was conducted to determine the nature of electro-dermal activity in a situation where a person evaluates several more or less close alternatives, choosing the most preferred one for him. We often find ourselves in such situations, choosing one or another product for purchase, which is a private copy of a certain category of goods. The final choice is influenced by many factors, both conscious (rational) and unconscious. In behavioral economics literature, the latter are often viewed as irrational components of choice. One cannot agree with this, if we take into account the fact that the unconscious contains, among other things, the whole experience acquired by a person in the process of his conscious activity. However, the question of the relationship between conscious and unconscious components in human behavior, in particular, being in a situation of choice, remains open. In the experiment described below, it was found out how objective (usually unconscious) indicators of choice correlate with those subjective assessments that accompany such a choice and which are reflected in behavioral, accessible to the awareness of human actions. The galvanic skin response (GSR, according to Feret) served as an indicator of the unconscious component of choice. The result of a conscious choice was recorded in the form of a mouse’s movement trajectory, controlled by the subject. The main conclusion is that the least preferred objects, the attractiveness of which is estimated to be significantly lower than the most preferred objects, cause stronger GSR, i.e. there is an inverse relationship between the amplitudes of the GSR and the estimates of the attractiveness of the objects. The hypothesis is formulated that the primary emotional response, reflected by unconscious visceral reactions, in the process of awareness is subjected to correction in the direction of positive values. Additional experiments are planned, including with the involvement of other indicators of emotional dynamics.

scholarly journals Cosmic Distribution of Optically Selected Quasars

1987 ◽  
Vol 124 ◽  
pp. 619-625
Author(s):  
Maarten Schmidt
Keyword(s):  
Luminosity Function ◽  
Birth Rate ◽  
Emission Lines ◽  
Short Life ◽  
Large Redshift ◽  
X Ray ◽  
Wide Range ◽  
X Ray Background ◽  
Spectral Survey ◽  
Luminosity Evolution

Counts of optically selected quasars as a function of magnitude and redshift show the effects of strong evolution. If quasars have relatively short life times, then the observed numbers at a given redshift are mostly determined by their birth rate and mean luminosity over their lifetime. In this case the evolution of the luminosity function can be described by density evolution, where the rate of evolution may depend on luminosity and other properties. On the other hand, if all quasars were formed at large redshift and have been decaying in luminosity since that time, then the evolution of the luminosity function is best described in terms of luminosity evolution. We discuss some of the consequences of luminosity evolution for the mass of quasars and for the X-ray background.We explore the observational aspects of the redshift cutoff of quasars. The situation is complicated by the unavoidable bias in slitless surveys against weak-line objects. Since quasar emission lines show a wide range of equivalent widths, a spectral survey will be characterized by a distribution of limiting continuum magnitudes rather than by a single value. The decline in the space density of quasars at large redshift may depend on luminosity, and may also have structure, such as a steep drop, but not a total cutoff, in density at a redshift near 3.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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