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At least 37 records · Page 2Linked to original sources

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↗

[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↗

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↗

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↗

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↗

[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↗

Solar activity.

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Internet↗

[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↗

[The human body response to factors related to solar activity variations].

The effect of nonstationary solar processes on human organism was studied. Daily measurements of electrical conductivity of 22 biologically active points on human skin, arterial pressure, and pulse frequency of 30 persons were performed, and their subjective sensations were registered. A comparative analysis of the data and variations in environment parameters, such as local A-index, atmospheric pressure, temperature, and indices of cosmic rays indicated a coincidence of their main periods. The conclusion is made that the reaction of the human organism on abrupt solar disturbances is biphasic and that there is a semiannual wave of synchronization of work of internal organs. The results are confirmed by simultaneous measurements in different cities.

Acupuncture Points↗

[Fluctuations in biophysical measurements as a result of variations in solar activity].

A theory is proposed to explain variations in the net electrical charge of biological substances at the Earth's surface. These are shown to occur in association with changes in the solar wind and geomagnetic field. It is suggested that a liquid dielectric's net volume charge will imitate pH effects, influence chemical reaction rates, and alter ion transfer mechanisms in biophysical systems. An experiment is described which measures dielectric volume charge, or non-neutrality, to allow correlation of this property with daily, 28-day, and 11-year fluctuation patterns in geophysical and satellite data associated with solar activity and the interplanetary magnetic field.

Biophysical Phenomena↗

Description, analysis and impact of major solar activity during recent U.S. Shuttle missions.

Since STS-26, three large solar events have occurred during Shuttle missions; a geomagnetic storm during STS-29 and solar particle events (SPEs) during STS-28 and -34. The maximum dose to a crew attributed to an SPE was estimated to be 30 microGy (70 microSv). Time-resolved dosimetry measurements of the SPE dose during STS-28 were made using the Air Force Radiation Monitoring Equipment (RME)-III. Comparison of calculated and measured dose demonstrated a discrepancy, possibly a result of deficiencies in the geomagnetic cutoff model used. This experience demonstrates that dose from an SPE is strongly dependent on numerous factors such as orbit inclination, SPE start time, spectral parameters and geomagnetic field conditions; the exact combination of these factors is fortuitous. New sources of data and procedures are being investigated, including real-time tracking of auroral oval positions or determination of particle cutoff latitudes, for incorporation into operational Shuttle radiation support practices.

Cosmic Radiation↗

[The determination of the radiation risk during an interplanetary space flight at different periods of solar activity].

Based on the own algorithm and Fortran calculation program the authors estimated radiation risk to cosmonauts on an interplanetary mission. They also analyzed the dependence of risk values on mission duration, space vehicle shield thickness, solar phase, and cosmonaut's age. The magnitudes of radiation risk to cosmonauts were compared with the national demographic risk of male lethality over a similar period of time.

Adult↗

[A possible biophysical mechanism of the solar activity effect on the central nervous system in man].

A biophysical mechanism of interaction between the man and environment is proposed, which treats these components as two correlated oscillation contours with discrete resonance frequencies. The coincidence of biocurrent frequencies of the human brain with the resonance frequencies of the cavity formed by the Earth surface and the lower ionosphere boundary allows one to consider the influence of solar flares on the human organism in terms of variations of the cavity frequencies due to changes in the parameters of its upper wall.

Atmosphere↗