Citzens of some countries need a visa to enter Brazil. Please check with a Brazilian consulate if this is your case. If needed, don't hesitate to ask for an invitation letter.
Brazilian currency is the REAL (R$, ISO code BRL). Today's exchange rate can be found here. Note that there are two different exchange rates, one for business (import and export), and another one for everything else (tourism). Avoid exchanging large amounts at the airport. There are ATM machines all over, as well as travel agencies where one can exchange money.
The international airport Tom Jobim is located at Ilha do Governador, an island in Guanabara bay, about 23 km from CBPF. Pre-paid taxi services can be found at the airport as one exits customs.
Moving around Rio is relatively easy. The best way is to use the abundant taxi service: yelow cars with a green sign (LIVRE) on the roof, when free. A taxi ride from Avenida Princesa Isabel to CBPF should cost no more than 10 reais (~2 euro). The subway system connects the northern and southern parts of the city, with some stations at downtown. The fare is 4.60 reais (~1 Euro).
Rio de Janeiro is located at time zone -3:00 GMT. In September, Rio will be 5 hours before Geneva and 1 hour later than New York.
PWA11/ATHOS6 will be held in the end of winter. Wheather in Rio is very pleasant at this time, with temperatures ranging from 18C to 28C. Although some rainy days are common in this period, the wheather is mostly sunny. Don't forget to bring your bathing clothes.
Electric power in Rio is 110V/60Hz. You may need an adaptor to connect your devices to Brazilian outlets.