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PubMedDate not supplied

[Estimates of the statistical characteristics of solar flares of cosmic radiation in the 20th and 21st cycles of solar activity].

This paper presents the principal characteristics of solar cosmic radiation events in the 20th and 21st cycles of solar activity. A uniform row of data concerning solar cosmic radiation has been obtained. An analysis of large-scale variations of the proton intensity time profile has demonstrated that the variations are associated with the structure of the interplanetary magnetic field which depends on interplanetary shock waves. The relative "proton" geoeffectiveness of the Sun southern hemisphere is significantly lower than of the northern hemisphere in both the 20th and the 21st cycles. Empirical distributions of standard characteristics of the SCR proton intensity profile and regression relations have been derived. They can be used to predict radiation parameters of SCR events.

Cosmic Radiation↗
PubMed2005

[Photoperiodism and brain strokes in years with low and high solar activity].

The paper demonstrates substantial (p = 0.95) increase of brain stroke (BS) rate during daylight hours, compared with that in the night-time hours. Such pattern is observed in accordance with astronomic seasons, half-year and year intervals: 1996 was a year with low solar activity (YLSA), 2000--a year with high solar activity (YHSA). Between the seasons "morning" and "day" during daylight hours and the seasons "night" and "day" in the night-time hours in YLSA the study revealed two biological turning-points, depending on the natural day length. In YHSA BS rate was the same in different seasons both during daylight hours and in the night-time hours. The variation of the BS rate within 24-hour time intervals demonstrates that the reference rate of Smolensk inhabitants for BS is season-dependent in YLSA, in comparison with that in YHSA; it is the highest in the seasons "morning" and "night" and the lowest in the seasons "evening "and "day". There is a weak correlation between BS rate and the physical phenomena under study (light and darkness). The results demonstrate possible direct biotropic effect of the light--darkness shift on BS rate in YLSA.

Adaptation, Physiological↗
PubMed1989

[The effect of solar activity on lunar changes in cardiovascular mortality].

After a 9-year follow-up of mortality due to cardiovascular emergencies (a total of 1,437 cases), the author found its frequency to be correlated with the moon phases. There are two maximum and minimum risk periods during lunation; the differences between them have a high statistical significance. The mortality study which registered the cases according to separate periods of maximum solar activity (spots, eruptions, etc.), medium and minimum activity recorded on three individual curves, showed that the maximum and minimum mortality curves were shifting in time phase so that during high solar activity, the minimum mortality was nearer to the new moon and full moon phases, while the maximum death rate approached the first and last lunar quarters; during the medium and low solar activities, the mortality maxima and minima were shifting counterclockwise the moon's orbit round the Earth, i. e. from the Earth's view with the Sun moving more and more to the west. The author offers some probable explanations for this phenomenon, which can help to make a more exact prognosis of critical days for patients with cardiovascular disorder. In addition, these findings can contribute to basic helio-geophysical research.

Cardiovascular Diseases↗
PubMedDate not supplied

[Correlation between the sizes of Drosophila populations and parameters of solar activity].

The relationship between the time series of the dynamics of the numbers of experimental populations of Drosophila melanogaster at the preimaginal stage and three heliogeophysical indices: Wolf numbers, the intensity of the 10.7-cm radio flux, and the Kp-index of geomagnetic activity was analyzed. Statistically significant data were obtained indicating that the dynamics of the number of the populations is related to the heliogeophysical factors, and this relationship depends on the phase of the 11-year cycle of solar activity. It was shown that the fertility of females and the survival of eggs is stimulated by factors associated with solar activity.

Animals↗
PubMed1975

Solar activity and mortality in the United States.

Mortality from all causes, from coronary heart disease, and from stroke in the US was studied in relation to solar activity as measured by the geomagnetic index, Ap, on a daily basis for the years 1964-66 and on a monthly basis for the years 1964-71. The data did not support previous assertions by Soviet researchers of an association between solar activity and cardiovascular mortality.

Astronomical Phenomena↗
PubMed2000

Cyclicity in incidence variations of meningococcal infections in Bulgaria is similar to that of solar activity.

This is a retrospective study on meningococcal meningitis (MM) in Bulgaria that has, for the first time, reported results on non-linear temporal patterns of incidence and its variations. Methods of descriptive statistics, linear and non-linear modelling as well as periodogram regression analysis have been applied. A non-linear decreasing trend in crude incidence rates per 100 persons over the years 1940-1990 has been described (p < 0.0001) and cyclic variations revealed (periods T = 8.00, 18.75, 24.75 and 33.50 years, p < 0.05-0.01). Above cycles have been detected after the reciprocal trend has been removed (y = 1.04 + 15.78/t). A similar cyclicity (periods T = 8.25 and 27.5 years) in the variations of solar activity (sunspot number Rz) over the same time interval of 51 years has been established after the main cycle of 10.5-13 years has been removed by a two-step procedure. The results from this study have added to our previous findings on cyclic variations in mortality and lethality from meningococcal infections in Bulgaria (1, 2). Above similarity is also in accordance with earlier conclusions on relations of solar activity cycles with epidemics of cerebrospinal meningitis in New York and USA over the years 1800-1935 (3, 4).

Bulgaria↗
PubMedDate not supplied

[Effect of variations of the geomagnetic field and solar activity on human physiological indicators].

The influence of changes in solar and geomagnetic activity on physiological parameters of man (EEG, pulse beat, rate of sensomotor reaction and the pressure in the period of spring equinox (10.02-10.04.96)) was investigated. The correlations between these parameters and variations in the Kp-index were obtained. It was found that the oscillations of the Kp-index and alpha-rhythm have identical periods.

Blood Pressure↗
PubMed1993

The carcinogenic effect of solar activity with different intensities on embryos.

The carcinogenic effects of solar activity with different intensities on embryos were studied epidemiologically. The study reveals that receiving a moderate amount of low level cosmic radiation at embryonic stage may reduce cancer occurrence later. This paper analyses and discusses the mechanisms of this hormetic effect.

China↗
PubMed1991

Admissions of patients with epileptic seizures (E) and dizziness (D) related to geomagnetic and solar activity levels: differences in female and male patients.

Admissions of 762 patients for epileptic seizures and 1553 for dizziness were studied for the connection with the level of monthly and yearly solar activity in the 11-year solar cycle and with four levels of daily geomagnetic activity levels (400 epileptic patients and 802 patients suffering with dizziness). The most significant differences of the studied groups were in the male/female ratio in different conditions of solar and geomagnetic activity. Changes in the group of epileptic patients were accompanied by similar, but adverse changes in the group suffering from dizziness. Different conditions of responses of females and males to environmental changes can explain the demonstrated results.

Adult↗
PubMed2002

The dependence of solar energetic particle fluxes in the Earth-Mars-Earth route on solar activity period.

This report presents the results of analyzing the relative importance of particle fluxes of different origin in the Earth-Mars-Earth route during different solar activity periods. The analysis has been made in terms of the galactic cosmic ray and solar energetic particle flux models developed at Moscow State University. The results demonstrate the extreme importance of the high-energy solar particle fluxes in interplanetary space even during the years of "quiet" Sun.

Cosmic Radiation↗
PubMed2001

The effect of solar activity on ill and healthy people under conditions of nervous (correction of neurous) and emotional stresses.

It is commonly agreed that solar activity has adverse effects first of all on enfeebled and ill organisms. In our study we have traced that under conditions of neurvous and emotional stresses (at work, in the street, and in cars) the effect may be larger (~ 30%) for healthy people. Our calculations have been carried out applying the epoch-superposition method, spectrum and correlation analyses to daily data over a 1992 to 1994 period from three independent databases (Kharkiv City) on patients (adults and children) suffering from mental diseases and physical traumas. The effect is most marked during the recovery phase of geomagnetic storms and accompanied by the inhibition in the central nervous system.

Adult↗
PubMedDate not supplied

[Prognosticaion of shigellosis and solar activity influence on the epidemic process].

The possibility of the quantitative prognostication of shigellosis morbidity with the use of the artificial neuron network (ANN), instructed by the reverse spread of error, was shown. On the basis of the available data the average error of the prognosis was approximately equal to 30%. Estimation of the influence on the shigellosis morbidity with solar activity the use of AN N presented no new arguments in favor of such influence.

Dysentery, Bacillary↗
PubMedDate not supplied

[Correlation of the width of annual tree rings with climatic changes and solar activity].

Fluctuations in the width of annual tree rings in the time interval from the eighth century till the present time were analyzed on the basis of dendroclimatic scales. Periods of extremely high and low growth of trees were distinguished, and their correlations with heliogeophysical factors were studied. The major climatic parameters determining the growth of trees are warmth and moisture; a small gain is observed in cold and droughty periods. No correlations between the width of tree rings and the minima and maxima of solar activity cycles were observed with the method used.

Climate↗
PubMed2000

Solar activity.

Explore the source record for details and available documents.

Internet↗
PubMedDate not supplied

[Correlation of the probability of occurrence of breast neoplasms with solar activity].

A contingent with high incidence of precancerous breast diseases (1080 persons) was studied to assess the relationship between solar activity and 1) alterations in the relationship between women with early menarche and women with middle and late menarche (high and low risk of breast cancer respectively) and 2) incidence of benign breast diseases. It was established that population content alterations were wave-like and had statistically significant periods 3,5; 7 and 12 years, and correlate with Wolf number changes. Incidence of benign breast diseases in the group aged 20-50 years also changed periodically (T = 11 years) depending on the birth-year and correlated conversely with Wolf numbers at the birth-years. Incidence of benign breast diseases changes periodically in the population of women with early menarche with the period of 3.6 years, and in those with middle and late menarche--with the periods of 10.5, 3.2 and 4 years. There is a statistically significant correlation between the incidence of benign breast diseases and Wolf numbers in population of women with middle and late menarche.

Breast Diseases↗