Scientific knowledge is increasing at a remarkable pace. In 2014, nearly 2.5 million peer-reviewed articles were published in 28 000 journals worldwide.¹ Once available only through subscription print services, many scientific articles are now published with an open access (OA) license. In contrast to subscription services, OA publishers shift costs for articles to authors to make content available to readers at no direct cost.² As of 2018, the Directory of Open Access Journals (http://www.doaj.org) reported more than 2.9 million articles published in more than 11 000 OA journals.

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开放获取发布中的挑战

科学知识正在以惊人的速度增长。2014年，在全球28000种期刊上发表了近250万篇经过同行评审的文章。¹一旦只能通过订阅打印服务获得，许多科学文章现在都以开放访问（OA）许可证发布。与订阅服务相反，OA出版商将文章的费用转移给作者，以使读者可以免费直接获得内容。²截至2018年，《开放获取期刊目录》（http://www.doaj.org）报告在超过11000种OA期刊中发表了超过290万篇文章。