This is the 14175th most frequent Russian word.
опубликованы
"Published."
The verb 'опубликованы' is in passive voice to indicate the action of making the articles publicly available, emphasizing the result.
Эти статьи были опубликованы в научных журналах.
These articles were published in scientific journals.
Here, 'опубликованы' conveys the status of documents which are currently made available for viewing.
Документы опубликованы для общего доступа.
The documents are published for public access.
Usage of 'опубликованы' here indicates a completed action of publishing performed by the research group.