Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Blockchain technology for a Safe and Transparent Covid-19 Vaccination   In late 2019, we witnessed the apparition of the covid-19 virus. The virus
appeared first in Wuhan, and due to people travel was spread worldwide.
Exponential spread as well as high mortality rates, the two characteristics of
the SARS-CoV-2 virus that pushed the entire world into a global lock-down.
Health and economic crisis, along with social distancing have put the globe in
a highly challenging situation. Unprecedented pressure on the health care
system exposed many loopholes not only in this industry but many other sectors,
which resulted in a set of new challenges that researchers and scientists among
others must face. In all these circumstances, we could attend, in a
surprisingly short amount of time, the creation of multiple vaccine candidates.
The vaccines were clinically tested and approved, which brought us to the phase
of vaccination. Safety, security, transparency, and traceability are highly
required in this context. As a contribution to assure an efficient vaccination
campaign, in this paper we suggest a Blockchain-based system to manage the
registration, storage, and distribution of the vaccines.

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The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas