At the beginning of my career in mathematical biology, I focused on forging relationships with Europe--Britain, Germany, Italy, and the Netherlands, just to name a few--but over the last decade, I shifted gears and began to seek closer ties with mathematical biology groups in Latin American countries such as Mexico, Argentina, Chile, and Colombia as well as other regions of the world. My recent trip to China only solidified the camaraderie I feel that all researchers have. Professional collaborations have always been an important part of scientific endeavors, so having the added benefit of doing international travel is one of the advantages of membership in academia. For me, meeting people from different cultures is always a thrilling event.
Cooperative Agreements and the Internationalization of Mathematics
In my opinion, the United States is the world center of internationalization efforts in the sciences because domestic universities continually create or strengthen international ties via collaborative agreements between groups or institutions. Our success as a nation in the sciences is no mystery; we attract and welcome the best.
Looking back at recent history, the biggest influx of foreign mathematicians took place just prior to World War II and was the result of Jewish mathematicians fleeing Nazism. This group of mathematicians led efforts that resulted in the creation of an American School of Mathematics (most became American citizens during the war).
Although Jewish mathematicians played a major role nationally, they helped to shape my career personally. Both my Ph.D. and postdoctoral advisors were children of Jewish immigrants: Fred Brauer  and Simon Levin , the winner of the 2004 Heineken Prize for Environmental Sciences . However, a new wave of émigrés from China enriched mathematics just a couple of decades ago. The Chinese Cultural Revolution  under Mao Zedong (1966-1976) seriously impacted life in Chinese universities and, consequently, brought many Chinese mathematicians to America in the 1970s and '80s. Many of the Chinese émigrés came as graduate students (as there were no advanced degrees in China before 1980). However, many were professional mathematicians who had no chance to carry out mathematical research during the Chinese Cultural Revolution (see box: The Mathematical Revolution Heads West).
The Mathematical Revolution Heads West
-- Daoxing Xia  is a functional analyst who has been at Vanderbilt University since 1984.
-- Weian Zheng  studies probabilities and is now at the University of California, Irvine.
Hospitality Was Invented in China
The Chinese are indeed gracious hosts offering the best food and accommodations to their foreign guests. The treatment and welcoming I received was extraordinary. We dined out every day and enjoyed at least 20 distinct dishes each day. I have pictures to prove it!
In addition, our hosts took us to visit some of the most impressive archaeological sites and museums in the world. In Beijing, I visited the greatest wonder of the world, the Great Wall. With a "driven" emperor urging his people on, the wall took millions of individuals several decades complete. In Shanghai, I felt at home because the surroundings reminded me of other great cities such as Buenos Aires, Paris, Rome, London, Mexico City, or New York City. What a treat!
I was delighted to visit two very distinguished institutions while I was there, Xi'an Jiaotong University  where I now hold the appointment of honorary professor and Shanghai Jiaotong University  (see box: Shanghai and Xi'an Jiaotong Universities). Speaking face-to-face with my associates rather than just talking to them via conference calls or Web casts was fantastic.
Shanghai and Xi'an Jiaotong Universities
Shanghai Jiaotong University , formerly the Nang Yang Public School, was founded in 1896 by Sheng Xuanhuai. It is one of the oldest universities in China. Around 1950, the institution split into five separate universities. The new campuses were located throughout China with one in Taiwan. Shanghai Jiaotong and Xi'an Jiaotong are two of the nine leading universities (Chinese government designation). Xi'an, my "home" institution now, has as its motto "rigor, integrity, determination, and loyalty" and as its mission to "become an internationally renowned research and comprehensive university." The histories of these institutions are intertwined and have a common root in Shanghai. The other offspring of Jiaotong University are Southwest Jiaotong, Northern Jiaotong, and Hsinchu Chiao Tung Universities (links to their Web sites are found at Shanghai's Web site).
Mathematical Biology at Xi'an Jiaotong University
The strongest group collaboration for me has been with the mathematical biology group at Xi'an Jiaotong University, founded and led over the past 20 years by Professor Ma Zhien. Because I had a long-term agreement between the mathematical biology group at Xi'an Jiaotong University and the Mathematical and Theoretical Biology Institute  (MTBI) at Cornell University (currently at Arizona State), several graduate students and professors from Xi'an Jiaotong held long- and short-term MTBI visiting positions. My most recent Cornell Ph.D. student, Baojun Song, is a former Xi'an Jiaotong faculty member who came to America under this agreement.
For the past 2 decades Xi'an Jiaotong's active group in mathematical biology has made important contributions in the areas of ecology, epidemiology, eco-toxicology, and immunology. Through the leadership of Professor Ma Zhien, this group has forged ties with well-established mathematical biology groups in the U.S. including those at the University of Tennessee, Knoxville, Cornell, and Arizona State. I was particularly impressed with the current work being conducted at Xi'an on SARS, the immunology of HIV, and the deliberate release of biological agents (relating to homeland security). In addition several women were heavily involved in mathematical research at Xi'an which shows that Chinese society is becoming a more open, equal-opportunity nation in the field of mathematics and its applications.
On to Shanghai Jiaotong University
My visit to Shanghai Jiaotong University brought me into Shanghai, the economic engine of China and one of the most modern and impressive cities in the world. While Xi'an gave me a view of China's grandiose past, Shanghai's splendor is a signal that the best may still be ahead.
Shanghai Jiaotong University is a large, modern university with a mathematics department containing over 80 faculty members. A glance at the wall posters of international mathematical conference/workshops hosted by the university speaks to the strong commitment Shanghai Jiaotong University has to the global sharing of knowledge. The environment seemed highly competitive and efforts by young faculty to search for grants to support their research in genomics, ecology, and epidemiology were evident.
My group does not have formal ongoing collaborations with this university, so one of my goals was to initiate and strengthen future collaborations between their strong dynamical systems group and MTBI. The growing interest in mathematical, theoretical and computational biology will make it possible to expand our interactions through various types of joint academic exchange programs.
Traveling and visiting other countries is part of my job and is a wonderful and necessary benefit. China once kept its doors closed to outside influences, but today the changes in China seem irreversible. A large percentage of citizens in Shanghai now drive new cars, own luxurious apartments, have heated discussions at Starbucks, watch CNN, and can buy anything that we have in America, but for much less. My Chinese friends who lived through the difficult times of the Chinese Cultural Revolution and who had to abandon their families to look for a better life are now returning to China or planning to move back after retirement. They all want to contribute to the betterment of research, particularly mathematical research in their native homeland.
Their nation is giving them back their right to do what they always wanted to do, build a better China for all. The problems that society faces today know no boundaries and talent knows no nationality. It is imperative that additional environments of scientific collaboration be fostered. China and the U.S. can contribute to human knowledge a lot more together than individually and collaboration agreements between groups of researchers with shared interests are the first step.
Carlos Castillo-Chavez is a Joaquin Bustoz Jr. Professor of Mathematical Biology at Arizona State University and may be reached at firstname.lastname@example.org .