Is the word publica the same in Brazilian and European Portuguese?

Yes

The word "publica" (the third-person singular present of the verb publicar) is identical in both Brazilian and Continental Portuguese regarding its spelling, grammar, and meaning. The only differences are phonetic, specifically in the pronunciation of the unstressed vowels and the overall rhythmic cadence. In Brazilian Portuguese, unstressed vowels (such as the final "a") are often more heavily reduced or neutralized, whereas in Continental Portuguese, the vowels tend to be articulated with a different melodic pattern and slightly more distinctness.

Brazilian Portuguese

1. Ela publica fotos no Instagram. (She posts photos on Instagram.)
2. A empresa publica o relatório hoje. (The company publishes the report today.)
3. O governo publica a nova lei. (The government publishes the new law.)
4. O autor publica seu novo livro. (The author publishes his new book.)
5. A revista publica uma matéria especial. (The magazine publishes a special feature.)

Continental Portuguese

1. Ela partilha fotos no Instagram. (She shares photos on Instagram.)
2. A empresa publica o relatório hoje. (The company publishes the report today.)
3. O governo publica o novo decreto. (The government publishes the new decree.)
4. O autor publica o seu novo livro. (The author publishes his new book.)
5. A revista publica uma reportagem especial. (The magazine publishes a special report.)