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Results for “Solar Activity”

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At least 19 recordsLinked to original sources
PubMed1993

Intraocular pressure (IOP) in relation to four levels of daily geomagnetic and extreme yearly solar activity.

The link between geomagnetic field activity (GMA), solar activity and intraocular pressure (IOP) in healthy individuals was investigated. The IOP of 485 patients (970 eyes) was recorded over three nonconsecutive years (1979, 1986, 1989) which were characterized by maximal solar activity (1979, 1989) or minimal solar activity (1986). The measurements were also correlated with four categories of GMA activity: quiet (level I0), unsettled (II0), active (III0), and stormy (IV0). Participants were also differentiated by age and sex. We found that IOP was lowest on days of level IV0 (stromy) GMA. The drop in IOP concomitant with a decrease in GMA level was more significant during periods of low solar activity and in persons over 65 years of age. There was a trend towards higher IOP values on days of levels II0 and IV0 GMA in years of high solar activity. Differences between the sexes and among individuals younger than 65 years were not significant. Our results show an interesting aspect of environmental influence on the healthy population.

Adult↗
PubMed1995

Solar activity cycle and the incidence of foetal chromosome abnormalities detected at prenatal diagnosis.

We studied 2001 foetuses during the period of minimal solar activity of solar cycle 21 and 2265 foetuses during the period of maximal solar activity of solar cycle 22, in all women aged 37 years and over who underwent free prenatal diagnosis in four hospitals in the greater Tel Aviv area. There were no significant differences in the total incidence of chromosomal abnormalities or of trisomy between the two periods (2.15% and 1.8% versus 2.34% and 2.12%, respectively). However, the trend of excessive incidence of chromosomal abnormalities in the period of maximal solar activity suggests that a prospective study in a large population would be required to rule out any possible effect of extreme solar activity.

Adult↗
PubMedDate not supplied

[The origin of the biological week from data on the rhythm of cardiac contractions in people during the solar activity cycle].

A human biologic week in the heart rate variations was compared with the variations of the sunspot area and geomagnetic activity over the solar cycle. The low ratio of amplitude of circaseptan rhythm to that of circadian rhythm in the heart rate of several clinically healthy men who did around-the-clock self-measurements in a number of years coincides with the period of anomalously low amplitude of circaseptan rhythm of the solar activity. Results herein suggest that physiologic circaseptan rhythms are built into the genome being adapted evolutionary to the original heliogeomagnetic environmental circaseptans.

Adaptation, Physiological↗
PubMed1995

Relationship between immunoglobulin levels and extremes of solar activity.

The possible relationship between epidemics and extremes of solar activity has been discussed previously. The purpose of the present study was to verify whether differences in the levels of immunoglobulins (IgA, IgG, IgM) could be noted at the highest (July 1989) and lowest (September 1986) points of the last (21st) and present (22nd) 11-year solar cycle. The work was divided into a 1-month study (covering the month of minimal or maximal solar activity), a 3-month study (1 month before and after the month of minimal or maximal solar activity) and a 5-month study (2 months before and after the month of minimal or maximal solar activity). A trend of a drop-off for all three immunoglobulins was seen on the far side of the maximal point of the solar cycle. Statistical significance was achieved in the 5-month study for IgM (P = 0.04), and a strong trend was shown for IgG (P = 0.07). Differences between the sexes were also noted.

Female↗
PubMed1990

[Solar activity and venereal disease morbidity].

Analysis of the solar activity and incidence of sexually-transmitted diseases over the period of 1954 through 1987 has revealed that development of fading of an epidemic process in sexually-transmitted diseases does not depend on enhancement or weakening of solar activity. These values much differ in respect of many parameters in various years, there is no correlation as regards the length of the periods between the minimal and maximal values or over these periods in various years. The morbidity rates are in inverse correlation with the activity of therapeutic and prophylactic institutions in detecting the patients during all types of prophylactic check-ups.

Cosmic Radiation↗
PubMedDate not supplied

[Solar activity, dynamics of the ozone layer and possible role of ultraviolet radiation in heliobiology].

Solar activity influences the ozonosphere thickness, thus changing the intensity of the near-Earth ultraviolet radiation in the B band. In certain regions the radiation may change by 10--15%, with solar activity varying from its maximum to minimum. The variations in the ultraviolet intensity are very likely to be environmentally important. Thus, solar ultraviolet radiation at lambda = 290 -- 340 nm acts as one more physical agent transferring the effect of solar activity into the biosphere.

Atmosphere↗
PubMed1983

Solar activity and myocardial infarction.

The correlation between the incidence of myocardial infarction, sudden cardiac death, the solar activity and geomagnetism in the period 1969-1976 was studied, basing on Wrocław hospitals material registered according to WHO standards; sudden death was assumed when a person died within 24 hours after the onset of the disease. The highest number of infarctions and sudden deaths was detected for 1975, which coincided with the lowest solar activity, and the lowest one for the years 1969-1970 coinciding with the highest solar activity. Such an inverse, statistically significant correlation was not found to exist between the studied biological phenomena and geomagnetism.

Adult↗
PubMed1995

[Variations of solar activity and radiation situation on board MIR station during the period 1986-1994].

This paper is dedicated to the analysis of the radiation situation onboard Mir station over a period of 1986-1994, there examined the main cosmophysics parameters and indices of the solar activity as well as the variations of the parameters of the earth's magnetic field and their association with the changes in the power of absorbed dose onboard the station. There noted the high levels of radiation exposure to the cosmonauts under terrestrial conditions when carrying out the roentgeno-radiologic examinations and procedures comparable or exceeding the absorbed doses during the flights. For revealing the regular associations of the radiation situation onboard the station with the parameters of solar activity there has been analyzed the time changes of average monthly values of dose power since the beginning of station functioning in 1986 until returning the fifteenth expedition to Earth. From the analyses of the results it might be assumed that the best statistical associations of average monthly power of the absorbed dose are found with the streams of protons of GCR. Wolff numbers and background stream of the radio emission of the Sun which reflects the existence of the radiation situation upon the phase of solar activity cycle. From this paper it transpires that calculating the dose loads during the period of the extreme phases of solar activity, it is possible to make between them the interpolations of time dependence by analogy with the dynamics in time of the background streams of GCR or Wolff numbers.

Data Interpretation, Statistical↗
PubMed1988

[Phase coordination of the rhythms of changes in solar activity and of the monthly biorhythms of altered cholesterol levels of the blood serum in rabbits].

The concentration of total, free and bound cholesterol in the blood serum of 13 intact Chinchilla male rabbits was determined in two four-month experiments carried out in 1973-1974 and in 1984-1985 during a "minimum" phase of an 11-year solar activity cycle. A hierarchy of ten cholesterol biorhythms and solar activity rhythms were singled out on a computer, using an original algorithm, in the individual changes in cholesterol concentration in each rabbit and in changes in seven environmental indexes. A statistical stability of the frequency and phase of low-frequency cholesterol biorhythms and solar activity rhythms has been established within an 11-year period, the fluctuation amplitude of the indexes studied being, on the contrary, statistically unstable.

Animals↗
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↗
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↗
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↗
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↗