Azadeh Mehrani, a graduate student in the University of Houston's chemistry department, said she knew leaving Houston to visit family in Iran last summer would be risky.

But she went anyway, gambling that she would quickly get another single-entry visa to return to the U.S. before the fall semester.

It took more than six months to get the document, which arrived last week - two days before President Donald Trump's executive action on immigration blocked citizens of seven majority-Muslim countries, including Iran, from entering the U.S.

Now, Mehrani is stuck in Tehran, for at least another 90 days.

"I'm so stressed right now - I'm not sure I can have my Ph.D. or not," said Mehrani, 30, in a phone interview from Tehran on Monday.

Trump's order reverberated across Texas campuses Monday, where 1,300 students from the seven countries on the list are enrolled at public colleges and universities, including 280 at UH. Thirty-two students at Rice University are affected.

Leaders at the state's schools are trying to determine which of their students, like Mehrani, were directly affected by Trump's order, but urged all students who are citizens of the seven countries to remain inside the U.S. as interpretations of the order continued to shift.

The action particularly resonated on campuses because they host students and faculty from all over the world.

Mehrani said she took the chance of going home because she hadn't seen her family in three years after leaving to pursue her dream of getting a Ph.D. in the U.S. On Monday, she said classmates have said they now feel "imprisoned" in the U.S. "Now our family cannot come and visit us … (and) you don't have permission to come out," she said.

The vast majority of students on Texas campuses affected by the order - most of whom come from Iran - remain inside the U.S.

"There's, naturally, concern and many questions," said Anita Gaines, director of UH's International Student and Scholar Services.

UH President and Chancellor Renu Khator said the university's immigration clinic is assisting the affected students.

University of Texas Chancellor William McRaven, a retired admiral who oversaw the mission that killed Osama bin Laden, said U.S. officials must clarify the order's intent.

"I would hope that my commitment to our nation's security cannot be questioned," McRaven said. "But, I also stand behind the core values we hold as a nation."

Later, he said that faculty, students and staff must travel on university business often. "We want them to return to the U.S. safely. We are and will remain committed to that principle, and to them."

More Information Number of students enrolled at Texas public universities from the seven banned countries: Iran: 974 Iraq: 137 Libya: 54 Somalia: 5 Sudan: 20 Syria: 45 Yemen: 57

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'Callous indifference'

In an email to students on Monday, Rice University President David Leebron said Rice would not reveal the immigration status, citizenship or national origin of any student, absent legal compulsion. The university will also develop a plan to give legal assistance to students denied entry because of their citizenship.

"These measures were implemented with a callous indifference to their immediate impact on individuals and their families," he said.

A Baylor College of Medicine physician, who asked to remain anonymous, is among those worried for her family. The naturalized citizen holds a second citizenship in Syria. If she leaves to visit family, will she be able to come back? She watches the news and scans the internet, but there are no clear answers. She did not want to give her name for fear of retaliation against family members still in war-torn Aleppo.

Alongside the travel ban, which applies to Syrian citizens, refugees from Syria have been banned from the U.S. indefinitely.

Her fears have centered on her elderly parents, 77 and 65 years old, who are in Houston for a visit that was supposed to be ending. They, too, have Syrian passports and have been living in Turkey after fleeing Aleppo. It took them two years of vetting to win permission to come to the U.S. to visit their daughter and grandchildren. Although they have a return ticket, they will probably cancel it.

"If they go, I'm not sure I'll ever get to see them again," said the doctor, among the dozens at Baylor impacted by the ripple effect of the executive order.

Dr. Paul Klotman, president and CEO of the medical school, sent out an institution-wide email on Sunday that said: "If anyone potentially affected by the order is scheduled to leave the county on business, please contact the Office of the General Counsel for guidance."

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As a Muslim, the physician is not buying the White House explanation that the executive order is not targeting those of her religion. "It's hard not to feel that way," she said, especially since officials have said that once the temporary ban is lifted, Christians will be given preference for entrance.

It distressing to her that people don't understand that people like her family are just as fearful of harm as those who seem to want to keep them out. "We all want safety," she said. "That's the reason my parents left Aleppo."

University of Houston-Downtown Interim President Michael Olivas, an immigration law and higher education law professor, said in a letter to students that the order is not entirely legally clear and may undermine "religion" as a predicate for asylum or refugee status.

"All bets are off until the courts rule or until Congress acts," he said. Three UH-Downtown students come from the seven countries named, he said.

University of Texas at Austin President Greg Fenves said there are 110 students and faculty members who are citizens of the seven countries banned in Trump's order.

He said that UT will keep in touch with those affected as the order is clarified. Teri Albrecht, director of UT's international student and scholar services office, said she was not aware of affected students who are abroad currently.

"We've gone through other major immigration (orders) in the past," Albrecht said, citing Sept. 11. "But we never had something as drastic as this … a blanket policy change. We don't have a lot of answers."

Rally of support

At Texas A&M University, 170 students enrolled in fall 2016 were from Iran, of 220 students from the seven banned countries. The university said it was not aware of any students who were out of the U.S. when the order was signed.

More than 900 people indicated they would attend an on-campus rally to support Muslim students on Monday evening, including students driving in from Sam Houston State University and UT, said organizer Mallory Chapman, a 19-year-old A&M freshman from Arlington.

Texas A&M University President Michael Young said in a statement that students should respect one another and stay informed.

"We are also working with our congressional delegation for assistance so that everyone affected by this order can continue their work without disruption or delay," he said.

Iraqi students in College Station now realize that they will likely not be able to visit home until they complete their programs, said Nabeel Al-Hakeem, a Texas A&M University graduate student.

Al-Hakeem hasn't been back to Iraq since 2014, when he left to study engineering at Texas A&M. Though Iraqi students and their spouses and children gather for holidays and other celebrations in College Station, homesickness is hard with such long stretches between visits.

Al-Hakeem called the order "disappointing" and said it would likely deter students from deciding to study in the U.S.

"The Iraqi people fight ISIS on behalf of all the world," he said, "and they don't deserve this kind of order by the American administration."

Jenny Deam and Ileana Najarro contributed to this report.