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Titel |
The threshold effects of Space and Terrestrial weather influence on human physiological parameters |
VerfasserIn |
Tamara Breus, Yurii Gurfinkel, Vadim Ozheredov, Tatyana Zhenchenko |
Konferenz |
EGU General Assembly 2011
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Medientyp |
Artikel
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Sprache |
Englisch
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Digitales Dokument |
PDF |
Erschienen |
In: GRA - Volume 13 (2011) |
Datensatznummer |
250055218
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Zusammenfassung |
The database containing 368 precedents consist of data on atmospheric temperature (T),
pressure (P), K-index of geomagnetic activity (predictors) and data of three –years
monitoring of healthy volunteer (adapter) by specially developed device TONOCARD were
used in this study. This device is intended for noninvasive measurements of arterial blood
pressure (BP), pulse wave velocity (PWV) and endothelial function (EF) [Gurfinkel et al.,
2009]. It is installed in medical unit of experimental complex of joint RUSSIA – ESA Project
MARS-500, and in one of the control groups of healthy volunteers accompanying this
experiment. Our studies are trial testing of this device. The objective of out study was to
determine the threshold values of individual parameters of terrestrial and space weather,
which causes the excess of negative effects associated with a significant increase or
decrease of aforementioned physiological parameters in relation to their normal
level. Search the threshold value that is the boundary of a half -bounded interval G
was carried out by optimizing the target functional, depending on a reference half
-bounded intervalÄ. The target functional is a difference of two mean random values
P(GË)ζ1 andP(~ GË)ζ2, where ζ1 (ζ2) is a physiological parameter (adaptor),
which predictor is in the region Ä (not in Ä), while P( )
GË (P( )
~ GË) is a prior
probability for predictor to get in Ä (not in Ä). Distributions of ζ1 and ζ2 values
are:
-« -«
pθ|ξ(z|x) pξ(x) dx pθ|ξ(z|x)pξ(x)dx
pζ1 (z) = ËG--«–––––– pζ2 (z) = ~ËG--«––––––,
pξ(x)dx pξ(x)dx
ËG ~ ËG
where ξ is a predictor, θ is an adaptor, pθ|ξ is a conditional probability. Proved that in case of
a reliable database the target functional Ψ( )
ËG = P( )
ËGζ1 - P( )
~ ËGζ2 reaches a
maximum only when Ä -¡ G. This fact makes it possible to determine the required threshold
values of terrestrial and space weather. Results: significant increase in the PWV
observed when the K-index is larger than 3.5, while all other parameters are not
depending on K-index. Lowering SBP begins in excess of atmospheric temperature
threshold of 22C0, the dependence of SBP from the atmospheric pressure is negligible.
PWV begins to exceed its average value after 15C0. As shown in [Breus et al.,
2010], PWV increases when temperature rises up to 20C0, and then ceases to grow. |
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