after the Committees on Appropriations of the Senate and the House of Representatives are notified of such transfer. 522. (a) None of the funds made available in this Act may be used to maintain or establish a computer network unless such network blocks the viewing, downloading, and exchanging of pornography. (b) Nothing in subsection (a) shall limit the use of funds necessary for any Federal, State, tribal, or local law enforcement agency or any other entity carrying out criminal investigations, prosecution, or adjudication activities. 523. None of the funds made available in this Act may be used by a Federal law enforcement officer to facilitate the transfer of an operable firearm to an individual if the Federal law enforcement officer knows or suspects that the individual is an agent of a drug cartel unless law enforcement personnel of the United States continuously monitor or control the firearm at all times. 524. None of the funds made available in this Act may be used to pay for the travel to or attendance of more than 50 employees of a single component of the Department of Homeland Security, who are stationed in the United States, at a single international conference unless the Secretary of Homeland Security, or a designee, determines that such attendance is in the national interest and notifies the Committees on Appropriations of the Senate and the House of Representatives within at least 10 days of that determination and the basis for that determination: Provided , That for purposes of this section the term international conference shall mean a conference occurring outside of the United States attended by representatives of the United States Government and of foreign governments, international organizations, or nongovernmental organizations: Provided further , That the total cost to the Department of Homeland Security of any such conference shall not exceed $500,000. 525. None of the funds made available in this Act may be used to reimburse any Federal department or agency for its participation in a