相关费用：选择性费用︾Gold open access.
The gold OA option is provided primarily for authors with research funding from an organization that mandates gold OA as a condition of publication and does not permit green OA as a route to compliance. The fee is $2,500. This request should be made at the time of submission, but not later than the time of acceptance. It is expected that the funder and the grant will be noted in the acknowledgments of the manuscript in the conventional manner. Articles published as gold OA are made available under a CC BY-NC license. If a CC BY or other license is required by your funding body, please notify the editorial office at the time you submit your manuscript. Articles published under a CC BY license are subject to an additional fee.