Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solar UV$-$B$/$A radiation is highly effective in inactivating
  SARS$-$CoV$-$2   Solar UV$-$C photons do not reach Earth's surface, but are known to be
endowed with germicidal properties that are also effective on viruses. The
effect of softer UV$-$B and UV$-$A photons, which copiously reach the Earth's
surface, on viruses are instead little studied, particularly on
single$-$stranded RNA viruses. Here we combine our measurements of the action
spectrum of Covid$-$19 in response to UV light, Solar irradiation measurements
on Earth during the SARS$-$CoV$-$2 pandemics, worldwide recorded Covid$-$19
mortality data and our 'Solar$-$Pump' diffusive model of epidemics to show that
(a) UV$-$B$/$A photons have a powerful virucidal effect on the
single$-$stranded RNA virus Covid$-$19 and that (b) the Solar radiation that
reaches temperate regions of the Earth at noon during summers, is sufficient to
inactivate 63\perc of virions in open$-$space concentrations (1.5 x 103
TCID50$/$mL, higher than typical aerosol) in less than 2 min. We conclude that
the characteristic seasonality imprint displayed world$-$wide by the
SARS$-$Cov$-$2 mortality time$-$series throughout the diffusion of the outbreak
(with temperate regions showing clear seasonal trends and equatorial regions
suffering, on average, a systematically lower mortality), might have been
efficiently set by the different intensity of UV$-$B$/$A Solar radiation
hitting different Earth's locations at different times of the year. Our results
suggest that Solar UV$-$B$/$A play an important role in planning strategies of
confinement of the epidemics, which should be worked out and set up during
spring$/$summer months and fully implemented during low$-$solar$-$irradiation
periods.

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The categories of this paper are: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
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The categories of this paper are: math
5
The categories of this paper are: gr-qc
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The categories of this paper are: cond-mat
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The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th