TrendMD (see also What is TrendMD?) is a large network of publishers cross-promoting articles, explained here. There are also other Knowledge Dissemination items such as sponsored tweets, which can be ordered by authors to maximize dissemination and impact of their work among different audiences and venues.
When you pay for the Article Processing Fee (APF) for your accepted paper, you can add options to your payment, which include for example extra dissemination through TrendMD or sponsored Tweets.
If the APF is already paid or waived, you can add this later by going to the following URL:
where 9999 should be replaced with the manuscript ID of your article.