The present regular issue consists of 10 works with a great variety of topics. It begins with two interesting health-related works: the first one, reviews different approaches that can help fight COVID-19 and the second one, tries to solve an optimal control problem of cancer treatment using an artificial neural network. It continues with algorithms that can help in industrial processes such as reducing the temperature of electronic circuits or carrying out chromium layer thickness forecast.

In this special issue, we want to gather some innovative applications that are currently pushing forward the research on Blockchain technologies. In particular, we are interested also in those applications that put the focus on the data, enabling new processes that are able to leverage relevant knowledge from the data. This special issue will be successful if readers gain a better understanding on how Blockchain can be applied to very diverse areas, and might even be interested in designing, implementing and deploying an innovative solution to a completely different field of knowledge.

The present regular issue starts with two articles related to one of the most relevant problems nowadays, which is the COVID-19 pandemic. Over the past years, there have been great advancements in health, but the evidence is that it remains a challenge to deal with pandemics and to achieve global health. IJIMAI has always reserved a space for heath topics and in the last years, a Special Issue on Big Data and e-health or a Special Issue on 3D Medicine and Artificial Intelligence were published.