共查询到20条相似文献,搜索用时 46 毫秒
1.
E. Giannaropoulou M. Papailiou H. Mavromichalaki M. Gigolashvili L. Tvildiani K. Janashia P. Preka-Papadema Th. Papadima 《Natural Hazards》2014,70(2):1575-1587
Over the last few years, various researches have reached the conclusion that cosmic ray variations and geomagnetic disturbances are related to the condition of the human physiological state. In this study, medical data concerning the number of incidents of different types of cardiac arrhythmias for the time period 1983–1992, which refer to 1902 patients in Tbilisi, Georgia, were used. The smoothing method and the Pearson r-coefficients were used to examine the possible effect of different solar and geomagnetic activity parameters and cosmic ray intensity variations on the different types of arrhythmias. The time interval under examination was separated into two different time periods, which coincided with the polarity reversal of the solar magnetic field occurred in the years 1989–1990, and as a result, a different behavior of all the above-mentioned parameters as well as of the different types of arrhythmias was noticed during the two time intervals. In addition, changing of polarity sign of the solar magnetic field was found to affect the sign of correlation between the incidence of arrhythmias and the aforementioned parameters. The primary and secondary maxima observed in the solar parameters during the solar cycle 22, also appeared in several types of arrhythmias with a time lag of about 5 months. 相似文献
2.
Papailiou M. Mavromichalaki H. Kudela K. Stetiarova J. Dimitrova S. 《Natural Hazards》2012,61(2):719-727
Aviation personnel exposure to cosmic radiation and its biological effects has been an interesting subject for research over
the last decade. In this study, scientific groups from Greece, Slovakia, and Bulgaria collaborated in order to examine the
potential effects of cosmic radiation on the cardiovascular functionality of a group of Slovak aviators. Specifically, daily
data concerning mean values of arterial diastolic and systolic blood pressure, which were registered during the medical examinations
of the group of aviators, were related to daily variations of cosmic ray intensity, as measured by the Neutron Monitor Station
on Lomnicky Stit. Statistical methods (analysis of variance—ANOVA and method of superimposed epochs) were applied in order
to establish a statistical significance (p-values) of the effect of cosmic ray intensity variations on the aforementioned physiological parameters not only on the days
of the events but also on the days preceding and following these events. Results reveal that diastolic and systolic blood
pressure can be influenced by changes in cosmic ray activity. 相似文献
3.
4.
Investigation into possible space weather hazards on cardiovascular system has been performed. A group of 14 healthy volunteers was examined in the spring of 2009 and 2 healthy persons performed electrocardiograph records for a period of 1 year everyday in the morning and in the evening. Results revealed that heart rate variability (HRV) parameters of the group varied strongly from the day before till 3 days after the registered weak storms during the time of investigation. Blood pressure and subjective psychophysiological complaints increased statistically significantly from 0 day till +2nd day. Heart rate (HR) of the group showed a trend for decrease. It was established that morning measurements were more sensitive to space weather variations in comparison with evening measurements. Both persons with prolonged registrations for a period of year did not reveal graded response to geomagnetic storms with different intensities. Both of them decreased HR during moderate storms, but they increased HR during major storms and on the days before and after these storms. HRV parameters varied significantly on these days. 相似文献
5.
The results of regular instrumental observations over geomagnetic field variations in the zones of influence of tectonic faults
during movement of seismic waves of varied intensity are presented. It has been shown that seismic waves with an amplitude
more than 5–10 μm/s, traveling across the fault zone, always produced geomagnetic field variations. At weaker seismic disturbances,
geomagnetic field variations are of the “glimmer” character, and the relative frequency of appearance of the effect drops
as the seismic wave amplitude decreases. The quantitative dependence between the maximal value of the full vector of variations
in geomagnetic field induction in a fault zone and the amplitude of the seismic disturbance has been found for the first time. 相似文献
6.
Geomagnetic storms are a natural hazard tohuman health in the Auroral Belt of the Circumpolar.Geomagnetic disturbances in space, and the associated short-term variations in the atmosphere and the geophysical environment,provoke a disturbance of nervous and cardiovascular systems in the human body. The Heart Rate Variability (HRV) method providesa momentary response of human organisms toshort-term geophysical perturbations related to the Polar Aurora. A pilot project was performed in the Murmansk region in 1997–1999 with a contemporaneous series of records for both HRV in a test group of local inhabitants and the variations of natural geomagnetic fields.A correlation between geomagnetic disturbances and heart rate was calculated and different reactions of people on geophysical impact were shown. The special group of `Aurora Disturbance Sensitive People' (ADSP) was revealed. Aninternational study, aimed atevaluation of the impact on human health due to exposure of northern populations to the geophysical risk factor (GRF) in the Circumpolar areas located under the Aurora Belt, is needed. 相似文献
7.
Narendra Bhandari 《Journal of Earth System Science》1986,95(2):183-191
Study of several cosmic ray effects, such as VH track density, spallogenic26Al and53Mn activity,21Ne and22Ne/21Ne ratio, made in the same sample or in cores taken from different meteorites can identify parameters related to the exposure history of meteorites and cosmic ray flux variations. Meteorites with single or multiple exposure can be distinguished from a track production rate —22Ne/21Ne correlation diagram and cosmic ray flux variations over 106–107 years can be deduced from a three-isotope correlation diagram of26Al,53Mn and21Ne. Isotopic data based on chondrites with simple, one-stage exposure are consistent with the same average galactic cosmic ray intensity over the past 2 million years as that during the past 107 years. 相似文献
8.
R P Kane 《Journal of Earth System Science》1986,95(1):1-12
Using the method of maximum entropy spectral analysis (MESA) by Burg and the least-squares linear prediction (lslp) (also calledFABNE) by Barrodale and Erickson, the spectra of geomagnetic indices Ap, AN, AS, AE, AU, AL, Dst and cosmic ray neutron intensity at Deep River are obtained for 1965 and 1969 from daily means and for longer periods from monthly means. A large number of peaks of periodicities from 2 days to several years is obtained, many of which are shown by all the indices. Some of these are probably harmonics of the 27 days solar rotation period and the 20–22 years double sunspot cycle period. Comparison is made with results of earlier workers who reported fewer peaks. 相似文献
9.
V. A. Alexeev 《Geochemistry International》2016,54(1):78-84
The distribution of the cosmic-ray exposure ages (T) of iron meteorites was analyzed to establish the possible variations in the intensity of the galactic cosmic ray (GCR) over the last billion years. The analysis was made for the entire data set containing ~80 age values from the literature (Voshage et al., 1983) and the corrected set after the exclusions of paired meteorites (using the Akaike information criterion). The dependence of the criterion χ2 in the distribution of the phase values Ph = T/t–int(T/t) on the values of the assumed period (t) of GCR variations was analyzed for both sets of meteorites. The significant deviations of these parameters from the respective average values were found for t ~ 400–500 Myr and, in part, for t ~ 150 Myr. These deviations were interpreted by numerical modeling using the values of ages randomly distributed in the range of 0–1000 Ma. It was found that for variations with a period of 450 Myr, the distribution of the phase values and cosmic-ray exposure ages in the model data set is similar to that of iron meteorites. These results testify to the existence of the GCR variations with a period of ~400–500 Myr during the last 1 Gyr. The variations in the GCR flux can be explained by periodic galactic spiral arm crossings of the solar system. The GCR variations with a period of ~150 Myr discussed in the previous studies (Shaviv, 2002; 2003; Scherer et al., 2006) appears to be less certain. 相似文献
10.
A.Yu. Kurazhkovskii N.A. Kurazhkovskaya B.I. Klain V.Yu. Bragin 《Russian Geology and Geophysics》2012,53(7):712-719
This study provides a compilation of the paleointensity records for the Cretaceous period derived from sediments of the Russian Plate and adjacent areas. The paleoinetensity values were calibrated using the laboratory redeposition experiments. Remarkable differences in the relative paleointensity variations were detected at the Berriasian–Early Barremian, Late Barremian–Santonian and Early–Late Maastrichtian boundaries. In the Berriasian–Early Barremian interval, the paleointensity varied stochastically, with the amplitude of about 1Ho and the mean value of 0.63Ho (Ho is the present-day geomagnetic field intensity assumed to be 40 μT). The records for the Barremian–Santonian give a picture of the geomagnetic field with alternating high- and low-amplitude features. The mean paleointensities remain constantly high (being on average 0.87Ho), and intervals of low-amplitude variation alternate with the pronounced bursts (3.5Ho). The Late Maastrichtian interval is characterized by high-amplitude paleointensity variations (4Ho) and a sharp drop towards the end of the interval. All records show remarkable similarities near the boundaries between geological time intervals, which are an increase in the amplitude and mean values of intensity at the end of intervals followed by a decrease towards the beginning of the subsequent interval. 相似文献
11.
A. Aldahan G. Possnert S. J. Johnsen H. B. Clausen E. Isaksson W. Karlen M. Hansson 《Journal of Earth System Science》1998,107(2):139-147
We report in this study the distribution of10Be in the top 40 m of the Renland ice core (East Greenland) and in a 30 m long core from DML (Dronning Maud Land, Antarctica)
for the period 1931–1988. The two sites show differences in10Be content, the Antarctica site showing smaller variance and a lower average10Be annual flux. Similarly, the average accumulation rate (cm water equivalent year−1) is higher in the Renland relative to DML. The variability in accumulation (precipitation) rates seems to explain part of
the difference in10Be flux between the two polar sites. Cyclic fluctuations of10Be flux correlate with the 11-year sunspot number and cosmic ray intensity than with the aa index (perturbation of the geomagnetic
activity by the solar wind). Our data corroborate10Be cyclic fluctuation pattern from the Dye 3 ice core and confirm a promising potential for correlation of global and local
events. 相似文献
12.
B.L.K. Somayajulu 《Geochimica et cosmochimica acta》1977,41(7):909-913
A critical evaluation of the available 10Be data shows that its concentration of marine sediments appears to be affected by climate, cosmic ray (C.R.) intensity variations, magnetic reversals and changes in sedimentation rates in that order. Possible variations in the C.R. intensity would have averaged ≦ ±30% for selected periods of the order of 105 yr during the last 2 m.y. 相似文献
13.
A.Yu. Kurazhkovskii N.A. Kurazhkovskaya B.I. Klain V.Yu. Bragin 《Russian Geology and Geophysics》2010,51(4):380-386
Published and new data on the Earth’s past magnetic field have been interpreted in terms of its links with the frequency of magnetic polarity reversals and with tectonic events such as plume-related eruptions and rifting. The paleointensity and reversal frequency variations show an antiphase correlation between 0 and 160 Ma, and the same tendency likely holds for the past 400 Myr. The geomagnetic field intensity averaged over geological ages (stages) appears to evolve in a linearly increasing trend while its variations increase proportionally in amplitude and change in structure. Both paleointensity and reversal frequency patterns correlate with rifting and eruption events. In periods of high rifting activity, the geomagnetic field increases (15 to 30%) and the reversals become about 40% less frequent. Large eruption events between 0 and 150 Ma have been preceded by notable changes in magnetic intensity which decreases and then increases, the lead being most often within a few million years. 相似文献
14.
We study the effect of solar activity on the incidence of myocardial infarction deaths (MID) in Mexico. We work with 129,917 cases along 1996–1999, grouping the data by sex and age, and considering the solar cycle phases. At higher frequencies the circaseptan is the most persistent periodicity in MID occurrence. During solar minimum the circaseptan period is not detectable compared with solar maximum. During Forbush decreases and geomagnetic activity, most cases present a higher average MID occurrence. Furthermore the MID rate is higher as the level of the geomagnetic perturbation increases. Male MID rates are in general higher than female rates and the difference increases as the geomagnetic perturbation increases. The age group with the lowest MID incidence is 25 to 44 years, the age group of 65 years is the most vulnerable. We conclude that solar activity does affect MID at low geomagnetic latitudes and that the solar maximum is the most hazardous time for MID incidence. 相似文献
15.
Eruptive activity of the Sun produces intensive fluxes of energetic particles and disturbances in geomagnetic field. It has been found that solar and geomagnetic activities affect the cardiovascular system. In this study, we investigated whether solar particle events (SPE) and geomagnetic storms (GS) affect risk of emergency hospitalization for first-time myocardial infarction (MI). The effect of environmental variables is analyzed separately for MI with and without elevation of ST segment in electrocardiogram. A case-crossover study design was used to analyze MI in 2,008 hospitalized patients at the Hospital of Kaunas University of Medicine, Lithuania, from January 1, 2004 to December 31, 2005. We evaluated the associations between SPE, GS, and daily number of emergency hospital admission for MI by Poisson regression, controlling for seasonal variation, weekdays, and meteorological factors. During days of SPE in conjunction with GS, the risk of hospital admissions for MI with ST elevation increased by 39?% (RR?=?1.39; 95?% CI 1.02?C1.91). Two days after SPE that going till GS, the risk of admission for MI without ST elevation increased by 54?% (RR?=?1.54; 95?% CI 1.05?C2.24). The major GS without increased proton flux with particle energies?>10?MeV does not increase the risk of admission for MI without ST elevation. Only GS occurred after SPE increased the risk of admission for MI without ST elevation. These findings suggest that SPE going till GS or SPE in conjunction with GS affect on cardiovascular system. The environmental factors have different effects on the risk of myocardial infarction with and without ST elevation. 相似文献
16.
Analysis of experimental observations of the Earth’s magnetic field variations recorded by the scientific instruments at the
Northern Caucasus Geophysical Observatory of the Institute of Physics of the Earth, Russian Academy of Sciences, in the period
2007–2009 was performed. It was found that the characteristic ultra-low-frequency (ULF) waveforms of the geomagnetic disturbances
were distinguished in the structure of the observed variations that reflect the process of preparation and development of
a tsunamigenic earthquake. 相似文献
17.
《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》2000,25(3):321-324
Variations of the air pressure, cosmic ray fluxes, sunspot numbers, and interplanetary magnetic field in connection with strong earthquake occurrences are studied. The results of this investigation permits one to consider the variations of the cosmic rays as one of the possible cause of air pressure variations and one of the possible earthquake precursors. 相似文献
18.
The results of instrumental observations have shown that the spectra of geomagnetic variations exhibit a quasi-harmonic component, the frequency of which is close to the basic spheroidal mode of the Earth 0S2. In periods 15 days long after three large earthquakes and in the absence of strong magnetic disturbances, the fine structure of this mode in geomagnetic variations is identified in the form of singlets. The frequencies of these singlets are similar to the theoretical values calculated using an ideal elastic isotropic model of the Earth of spherical symmetric form without its rotation.
相似文献19.
A series of yearly data on the concentration of radioactive carbon 14C in tree rings measured at the Tbilisi State University in 1983–1986 and covering the time interval 1600–1940 is statistically analyzed. We find evidence for a 22-year cyclicity in the intensity of Galactic cosmic rays (GCRs) during the Maunder minimum of the solar activity (1645–1715), testifying that the solar dynamo mechanism continued to operate during this epoch. Variations of Δ14C on timescales of tens and hundreds of years correlate well with the corresponding variations of the GCR intensity and solar activity, making radiocarbon a reliable source of information on long-timescale variations of solar activity in the past. Short-timescale (<30 years) fluctuations of Δ14C may be appreciably distorted by time variations not associated directly with solar activity; probable origins of this distortion are discussed. 相似文献
20.
A. G. Tlatov 《Astronomy Reports》2006,50(4):325-332
The characteristic time scales for variations in the differential rotation of the solar corona are determined using measurements of the intensity of the FeXIV 5303 Å coronal line made from 1939–2004. Drift waves of the variations in the rotational speed with an 11-year periodicity can be distinguished. Moving averages with time intervals from two to five years are used to identify torsional waves. In addition, longer-period variations in the rotational speed can be distinguished when longer averaging intervals are used. When the interval used for the moving average is increased to 8–12 years, a quasi-22-year rotational period appears. The low-latitude corona rotates more slowly in odd cycles than in even cycles. Increasing the duration of the averaging interval further shows that rapid rotation at low latitudes was observed in 1940–1950 and 1990–2000, while slow rotation was observed in 1960–1980, possibly suggesting the presence of a 55-year period in the rotational variations. Long-term variations are found in the rotation of polar regions. The rotational variations for high-latitude corona are in antiphase with those for the low-latitude corona. The origins of zones of anomalous coronal rotation and their dynamics in the global activity cycle are discussed. 相似文献