  Pinpointing the neutrino sources is crucial to unveil the mystery of
high-energy cosmic rays. The search for neutrino-source candidates from
coincident neutrino-photon signatures and electromagnetic objects with peculiar
flaring behaviors have the potential to increase our chances of finding
neutrino emitters. In this paper, we first study the temporal correlations of
astrophysical flares with neutrinos, considering a few hundreds of
multi-frequency sources from ALMA, WISE, Swift, and Fermi in the containment
regions of IceCube high-energy alerts. Furthermore, the spatial correlations
between blazars and neutrinos are investigated using the subset of 10-year
IceCube track-like neutrinos with around 250 thousand events. In the second
test, we account for 2700 blazars with different types of flaring phases in
addition to sole position. No significant neutrino emissions were found from
our analyses. Our results indicate an interesting trend showing the infrared
flaring stages of WISE blazars might be correlated with arrival times of the
neutrino alerts. Possible overflow of neutrinos associated with two of our
blazar sub-samples are also illustrated. One is characterized by a significant
flaring lag in infrared with respect to gamma-rays, like seen for TXS0506+056,
and the other is characterized by highly simultaneous infrared and gamma-ray
flares. These phenomena suggest the need to improve current multi-frequency
light-curve catalogs to pair with the advent of more sensitive neutrino
observatories.
