Research Articles (up to ~4500 words, Including references, notes and captions, or ~5 journal pages) are expected to present a major advance. Research Articles include an abstract, an introduction, up to six figures or tables, sections with brief subheadings, and a maximum of 40 references. Materials and Methods should usually be included in supporting online material, which should also include information needed to support the paper's conclusions.
Reports (up to ~2500 words or ~3 journal pages) present important new research results of broad significance. Reports should include an abstract, an introductory paragraph, up to four figures or tables, and a maximum of 30 references. Materials and Methods should usually be included in supporting online material, which should also include information needed to support the paper's conclusions.
Reviews (4 journal pages, on average) describe new developments of interdisciplinary significance and highlight unresolved questions and future directions. All Reviews undergo peer review. They include an abstract, an introduction that outlines the main point, and brief subheadings. A maximum of 40 references is suggested. Most Reviews are solicited by the editors, but unsolicited submissions may also be considered
研究論文では、参考文献（40本以内）と図表（6枚以内）の説明、注記も含めて4500 words以内。Abstract, Introductionに続いて、sections with brief subheadings （小見出しを付けたセクション、Results & Discussionに相当）とあります。Materials and Methods はWebに記載され、印刷はされません。レポートは、やや格下の位置づけのようですね。
Abstractsexplain to the general reader why the research was done and why the results are important. They should start with some brief BACKGROUND information: a sentence giving a broad introduction to the field comprehensible to the general reader, and then a sentence of more detailed background specific to your study. This should be followed by the RESULTS, or if the paper is more methods/technique oriented an explanation of OBJECTIVES/METHODS and then the RESULTS. The final sentence should outline the main CONCLUSIONS of the study, in terms that will be comprehensible to all our readers. The abstract should be 125 words or less.