Even before the failed coup, scientists in Turkey did not have it easy. In contrast to Germany, where universities and research institutions are protected by independent supervisory bodies, in Turkey, the government can legally intervene all the way into lecture halls, research labs and university libraries.

The Turkish Council of Higher Education (YÖK), which was founded after the previous military coup of 1980, subjects universities to direct government control - one reason why the ruling Justice and Development Party (AKP) was able to implement hash penalties against university heads, deans, professors and lecturers following July's failed coup.

Measures, which included sacking teachers, professors and closing down some schools and universities. Following the coup attempt, and President Recep Tayyip Erdogan declaring a state of emergency in the country, it was reported a number of university professors were also being held in custody - although it remains unclear what they have been charged with.

Restrictions of scientific liberties are nothing new

For years, the Turkish government has removed disagreeable university heads. In recent weeks, Ankara issued a temporary travel ban on all university employees. It affected not only professors, but also many postgraduate students. That order was revoked on July 22.

"The threshold in Turkey is very low. Even many doctoral students have employment contracts with the government, rather than stipends," explains Stephan Geifes, head of the Turkey exchange program with the Germany Academic Exchange Service (DAAD). "These people are employees of the university and therefore subject to such restrictions," he adds.

The latest purges cast a shadow over German-Turkish scientific cooperation. "It hits us so hard, because we do have such close relations with Turkey in the scientific field," Geifes says.

Research cooperations have been put into question, Horst Hippler warns

Professor Horst Hippler, president of the German Rectors' Conference, a body comprising of German university heads, agrees. "A small interruption will never do much harm, but if this continues much longer, it could mean the end for many cooperation projects," says. The consequences, he fears, will be visible in the future. "A situation of insecurity will not encourage scientists to sign common applications for research grants," he adds.

Turkey and Germany are closely intertwined

Some figures illustrate the existing strong links between Germany and Turkey. Ninety students from Turkey are currently receiving DAAD stipends in addition to 12 doctoral students and one university professor. And there are 55 students participating in summer lectures, such as intensive language courses.

Numbering 30,000, Turkish students top of the list of foreign scholars studying in Germany. This figure, however, also includes those who grew up and went to school in Germany, but have, for whatever reason, chosen to retain a Turkish passport.

The interest goes both ways. In 2015 there were 3,025 young people from Germany studying in Turkey. About 2,600 of them receiving Erasmus-Plus stipends from the European Union.

No limitations for students

The latest restrictions set down by Ankara do not affect students directly. "Turkish students can leave the country freely and German students can travel to Turkey," DAAD regional expert Geifes explains. But the purges of the university staff can lead to a situation where studying becomes less attractive.

Turkey is hurting itself by restricting the liberty of science, Enno Afderheide says

And even though the consequences for many of those affected may not be clear for some time to come, many observers from Germany's large science organizations believe the purges may have devastating results.

"This is a catastrophe for the scientific cooperation between Turkey and Germany, and also for the integration of Turkey in international research," Enno Aufderheide, secretary general of the Alexander von Humboldt Foundation (AvH), says.

The AvH supports top scientists with research stipends, meaning they can attend German universities and other scientific institutions as guests and use research facilities while working with German research partners.

Exile for persecuted scientists

In 2014 the AvH launched the Philipp-Schwartz initiative. It was originally meant as a support program for persecuted scientists from totalitarian regimes, such as Syria or from countries in northern Africa or Asia.

"We were surprised ourselves to see that Turkey became the second largest country of origin," Aufderheide says. "This shows that the conditions for scientists were even bad before." Giving an example, he says, "about 1,000 scholars who signed a petition demanding an end to the civil war in the Kurdish parts of Turkey have since been politically persecuted."