Submission guidelines

Online submission
 

All manuscripts must be submitted via our online submission system using the Submit manuscript link. Using this system, authors can upload manuscript files (text, figures, videos) directly to our office and check on the status of their manuscripts during the review process. In addition, Reviewers can access the manuscript online, which speeds up the review process. Revised manuscripts should be uploaded via the link provided in the Editor's decision letter. Please do not submit revisions as new manuscripts.

Before a manuscript is submitted, please review our Editorial policies, and ensure that the submission complies with our policy requirements.

Large Language Models (LLMs), such as ChatGPT, do not currently satisfy our authorship criteria. Notably an attribution of authorship carries with it accountability for the work, which cannot be effectively applied to LLMs. Use of an LLM should be properly documented in the Methods section (and if a Methods section is not available, in a suitable alternative part) of the manuscript. In response to emerging information, advice, guidance and policy around artificial intelligence (AI), we have created a dedicated AI section in our Editorial Policy page. Please familiarize yourself with this content and comply with relevant policies.
 

ORCID
 

ORCID for corresponding authors

As part of our efforts to improve transparency in authorship, we ask all corresponding authors of accepted papers to provide their Open Researcher and Contributor Identifier (ORCID) ID, before submitting the final version of the manuscript.

To do this, the corresponding author will need to:

  1. Log in using this link: Submit manuscript
  2. Click 'Modify My Springer Nature Account'
  3. Under the ‘Personal Profile’ tab, click ‘Create/link an Open Researcher Contributor ID (ORCID)'
If you have an ORCID account, enter your ORCID email and password.

If you don’t have an ORCID account, you can create one at this stage.

Non-corresponding authors do not have to link their ORCID but are encouraged to do so.

Linking ORCID and Springer Nature accounts can be done at any time prior to acceptance.

Please note that it is not possible to add/modify ORCID details at proof stage. For more information please visit ORCID at Springer Nature. If you experience technical issues please contact the Platform Support Helpdesk.
 

Submission policies
 

Submission to npj Cardiovascular Health is taken to imply that there is no significant overlap between the submitted manuscript and any other papers from the same authors under consideration or in press elsewhere. (Abstracts or unrefereed web preprints do not compromise novelty). The authors must include copies of all related manuscripts with any overlap in authorship that are under consideration or in press elsewhere. If a related manuscript is submitted elsewhere while the manuscript is under consideration at npj Cardiovascular Health, a copy of the related manuscript must be sent to the Editor.

The primary affiliation for each author should be the institution where the majority of their work was done. If an author has subsequently moved, the current address may also be stated.

If the manuscript includes personal communications, please provide a written statement of permission from any person who is quoted. E-mail permission messages are acceptable.

Follow this link for further information on the review process and how Editors make decisions.

After acceptance, changes to the manuscript may be made so that papers conform to our style. The corresponding author is sent proofs and is welcome to discuss changes with the Editors, but npj Cardiovascular Health reserves the right to make the final decision about matters of style and the size of figures.

The Editors also reserve the right to reject a paper even after it has been accepted if it becomes apparent that there are serious problems with the scientific content or with violations of our publishing policies.
 

General information for preparing manuscripts
 

This guide outlines key points for preparing primary research manuscripts for submission to npj Cardiovascular Health.

The corresponding author should be familiar with the journal’s Editorial policies and is solely responsible for communicating with the journal and managing communication between coauthors. Before submission, the corresponding author ensures that all authors are included in the author list and agree with its order, and that they are aware the manuscript is to be submitted.
 

Reporting summary and editorial policy checklist
 

Research articles in Life Sciences, Health Sciences, Earth and Environmental Sciences, and Social and Behavioural Sciences must include relevant details about several elements of experimental and analytical design. These requirements aim to improve the transparency of reporting and the reproducibility of published results. They focus on elements of methodological information that are frequently poorly reported (see more details on these elements here). You will be asked to complete and submit the Nature Portfolio Reporting Summary together with the revised version of your manuscript after peer-review. Please see our editorial policies page for details and to download the Reporting Summary document.

The reporting summary will be published with all accepted manuscripts. All authors must also complete an editorial policy checklist to ensure compliance with Nature Portfolio editorial policies.

Other checklists

If your manuscript is sent for peer-review, you will also be asked to complete the Nature Portfolio Editorial Policy Checklist. This checklist is not sent to the Reviewers but must be received by the Editors before the paper can be sent for peer-review. A copy of the checklist can also be downloaded on our policies page.

Authors are encouraged to include both completed forms at the time of submission.

The Reporting Summary will be published as a Supplementary File alongside all primary research articles in Life Sciences, Health Sciences, Physical Sciences, Applied Sciences, or Society & the environment accepted from January 2019.
 

Cover letter
 

Authors should provide a cover letter that includes the affiliation and contact information for the corresponding author. The cover letter is an excellent opportunity to briefly discuss the context and importance of the submitted work and why it is appropriate for the journal. Please avoid repeating information that is already present in the abstract and introduction. The cover letter is not shared with the referees, and should be used to provide confidential information, such as conflicts of interest, and to declare any related work that is in press or submitted elsewhere. It is also appropriate to include suggested or excluded referees in the cover letter. We strive to ensure that the diversity of our Reviewers reflects that of the broad scientific community, in terms of gender, ethnicity/race, geographic location and career stage. We ask that you keep this in mind when suggesting potential Reviewers.
 

Format of manuscripts
 

Manuscripts submitted to npj Cardiovascular Health do not need to adhere to our formatting requirements at the point of initial submission; formatting requirements only apply at the time of acceptance. 

We encourage authors to incorporate the manuscript text and figures into a single PDF or Microsoft Word file. Suitably high resolution figures may be inserted within the text at appropriate positions or grouped at the end. Each figure legend should be presented on the same page as its figure. We can accept LaTeX files at the acceptance stage, but before then please supply compiled PDFs.

Manuscripts published in the npj Series journals are not subject to in-depth copy editing or display item redrawing as part of the production process. Authors are encouraged to seek copy editing or language editing services for their manuscripts, either before submission or at the revision stage, should they feel it would benefit their manuscript. Such services include those provided by Springer Nature Author Services and American Journal Experts. Please note that the use of any editing service is at the author's own expense and in no way implies that the article will be selected for peer review or accepted for publication.
 

Methods
 

Authors must ensure that their Methods section includes adequate experimental and characterization data necessary for others in the field to reproduce their work. Please refer to our editorial policies for more information. Descriptions of standard protocols and experimental procedures should be given. Commercial suppliers of reagents or instrumentation should be identified. Sources for kits should be identified. Experimental protocols that describe the synthesis of compounds should be included. Authors should describe the experimental protocol in detail, referring to amounts of reagents in parentheses, when possible (e.g. 1.03 g, 0.100 mmol). Standard abbreviations for reagents and solvents are encouraged. Safety hazards posed by reagents or protocols should be identified clearly. Isolated mass and percent yields should be reported at the end of each protocol. The Methods section should be subdivided by short bold headings referring to methods used and we encourage the inclusion of specific subsections for statistics, reagents and animal models.

We encourage authors to deposit the step-by-step protocols used in their study in www.protocols.io, Springer Nature's open repository of scientific protocols. Protocols deposited by the authors will be linked to the online Methods section upon publication.
 

References
 

References are numbered sequentially as they appear in the text, methods, tables, figure legends. Only one publication is given for each number.

Only papers that have been published or accepted by a named publication or recognized preprint server should be in the numbered list. Meeting abstracts that are not published and papers in preparation should be mentioned in the text with a list of authors (or initials if any of the authors are co-authors of the present contribution). Published conference abstracts, numbered patents and research datasets may be included in the reference list. When referencing a dataset, a DOI or accession code should be included in the citation where available. URLs for web sites should be cited parenthetically in the text, not in the reference list; articles in formal, peer-reviewed online journals should be included in the reference list. Grant details and acknowledgments are not permitted as numbered references. Footnotes are not used.

The npj Series journals use standard Nature referencing style. All authors should be included in reference lists unless there are more than five, in which case only the first author should be given, followed by 'et al.'. Authors should be listed last name first, followed by a comma and initials (followed by full stops) of given names. Article titles should be in Roman text, the first word of the title should be capitalized and the title written exactly as it appears in the work cited, ending with a full stop. Book titles should be given in italics and all words in the title should have initial capitals. Journal names are italicized and abbreviated (with full stops) according to common usage. Volume numbers and the subsequent comma appear in bold.

Published papers:

Printed journals:
Schott, D. H., Collins, R. N. & Bretscher, A. Secretory vesicle transport velocity in living cells depends on the myosin V lever arm length. J. Cell Biol. 156, 35-39 (2002).

Online only:
Bellin, D. L. et al. Electrochemical camera chip for simultaneous imaging of multiple metabolites in biofilms. Nat. Commun. 7, 10535; 10.1038/ncomms10535 (2016).

For papers with more than five authors include only the first author’s name followed by ‘et al.’.

Books:
Smith, J. Syntax of referencing in How to reference books (ed. Smith, S.) 180-181 (Macmillan, 2013).

Online material:
Manaster, J. Sloth squeak. Scientific American Blog Network http://blogs.scientificamerican.com/psi-vid/2014/04/09/sloth-squeak (2014).

Hao, Z., AghaKouchak, A., Nakhjiri, N. & Farahmand, A. Global integrated drought monitoring and prediction system (GIDMaPS) data sets. figshare http://dx.doi.org/10.6084/m9.figshare.853801 (2014).
 

Author contributions
 

The npj Series journals require an Author Contribution Statement that specifies the individual contributions of each co-author. 

Please use initials to refer to each author's contribution in this section, for example: "FC analyzed and interpreted the patient data regarding the hematological disease and the transplant. RH performed the histological examination of the kidney, and was a major contributor in writing the manuscript. All authors read and approved the final manuscript.

 

Acknowledgements
 

Acknowledgements should be brief, and should not include thanks to anonymous Reviewers and Editors, or effusive comments. Relevant grant or contribution numbers should be included.

Funding information should be placed in the Acknowledgement section. When acknowledging funding, our recommended best practice is that authors should acknowledge funders and grants on publications when the activities that contributed to that publication are within scope of the acknowledged grant and arise directly from a specific grant. The role of the funding body in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript should also be declared. If the funder has played no role in the research, this should be stated. 

Declaring funding in the Acknowledgments can take one of the following forms: 

  • This study was funded by [funder name] [grant number where applicable]. The funder played no role in study design, data collection, analysis and interpretation of data, or the writing of this manuscript. 

  • This study received no funding.

 

Competing interests
 

A competing interests statement is required for all accepted papers published in the npj Series journals. If there is no competing interest, a statement declaring this is still required.

Competing interests may take one of the following forms (or a combination of more than one):

 
  • All authors declare no financial or non-financial competing interests. 

  • Author IJ holds shares in [company name A] but and declares no non-financial competing interests. Author KL has previously acted as a paid consultant for [company name B] but declares no non-financial competing interests. All other authors declare no financial or non-financia competing interests. 

  • Authors AB, EF, GH declare no financial or non-financial competing interests. Author CD serves as [Editor role title] of this journal and had no role in the peer-review or decision to publish this manuscript. Author CD declares no financial competing interests.
     

Data availability
 

npj Cardiovascular Health requires a Data Availability Statement to be included in the submitted manuscript (see the section on availability of materials and data in our editorial policies page for more information).

Data availability statements should provide a statement about the availability of the minimal dataset that would be necessary to interpret, replicate and build upon the methods or findings reported in the article. Data availability statements should be provided as a separate section after the Methods section before the References, under the heading "Data Availability".
 

Data availability statements can take one of the following forms (or a combination of more than one if required for multiple datasets):

 
  • The datasets generated and/or analysed during the current study are available in the [insert name of repository] repository, [insert persistent URL to datasets]. 

  • The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.

  • All data generated or analysed during this study are included in this published article [and its supplementary information files].

  • The datasets generated and/or analysed during the current study are not publicly available due to [INSERT REASON WHY DATA ARE NOT PUBLIC] but are available from the corresponding author on reasonable request.

  • Data sharing is not applicable to this article as no datasets were generated or analysed during the current study.

  • The data that support the findings of this study are available from [third party name] but restrictions apply to the availability of these data, which were used under licence for the current study, and so are not publicly available. Data are however available from the authors upon reasonable request and with permission of [third party name].
     

Code availability
 

Any previously unreported custom computer code or scripts used to generate results reported in the manuscript that are central to the main claims must be made available to Editors and referees upon request. Any practical issues preventing code sharing will be evaluated by the Editors who reserve the right to decline the manuscript if important code is unavailable. At publication, Nature Portfolio journals consider it best practice to release custom computer code in a way that allows readers to repeat the published results.

For all studies using custom code that is deemed central to the conclusions, a statement must be included in the Methods section, under the heading "Code availability", indicating whether and how the code can be accessed, including any restrictions.

Code availability statements can take one of the following forms (or a combination of more than one if required):

  • The underlying code [and training/validation datasets] for this study is available in [repository name] and can be accessed via this link [insert persistent URL to code]. 

  • The underlying code for this study [and training/validation datasets] is not publicly available for proprietary reasons. 

  • The underlying code for this study [and training/validation datasets] is not publicly available but may be made available to qualified researchers on reasonable request from the corresponding author.
     

Supplementary information
 

Any Supplementary Information should be submitted with the manuscript and will be sent to referees during peer review. It is published online with accepted manuscripts. We request that authors avoid "data not shown" statements and instead make their data available via deposition in a public repository (see 'Reporting standards and availability of data, materials, code and protocols' for more information). Any data necessary to evaluate the claims of the paper that are not available via a public depository should be provided as Supplementary Information.

All supplementary information cited in the manuscript should be provided in a separate, single merged PDF. The journal does not edit Supplementary Information files; they will be uploaded with the published article as they are submitted with the final version of your manuscript, any tracked changes should be removed from the file. The journal does not permit Supplementary Methods, all Methods should be reported in the main manuscript file.

If supplementary tables are too large (or excel files) to be included in the Supplementary PDF file, you should provide them separately as Supplementary Data and ensure that they are labelled in "Supplementary Data XX" format and not as ‘Supplementary Table’. Provide corresponding Title and Legend in the Supplementary PDF file. Ensure to cite them consistently as they are labelled.

Supplementary Information is not edited, typeset or proofed, so authors should ensure that it is clearly and succinctly presented at initial submission, and that the style and terminology conform to the rest of the paper. Please note that modification of Supplementary Information after the paper is published requires a formal correction, so authors are encouraged to check their Supplementary Information carefully before submitting the final version.

Further queries about submission and preparation of Supplementary Information should be directed to the editorial team. Please visit our contact page
 

General figure guidelines
 

Authors are responsible for obtaining permission to publish any figures or illustrations that are protected by copyright, including figures published elsewhere and pictures taken by professional photographers. The journal cannot publish images downloaded from the internet without appropriate permission.

Unnecessary figures should be avoided: data presented in small tables or histograms, for instance, can generally be stated briefly in the text instead. Figures should not contain more than one panel unless the parts are logically connected; each panel of a multipart figure should be sized so that the whole figure can be reduced by the same amount and reproduced at the smallest size at which essential details are visible.

Should your manuscript be accepted, you will receive more extensive instructions for final submission of display items. However, some guidelines for final figure preparation are included below if you wish to minimize later revisions and possible delays.

Figures should be numbered separately with Arabic numerals in the order of occurrence in the text of the manuscript. When appropriate, figures should include error bars. A description of the statistical treatment of error analysis should be included in the figure legend. Please note that schemes are not used; sequences of chemical reactions or experimental procedures should be submitted as figures, with appropriate captions. A limited number of uncaptioned graphics depicting chemical structures—each labeled with their name, by a defined abbreviation, or by the bold Arabic numeral—may be included in a manuscript.

Figure lettering should be in a clear, sans-serif typeface (for example, Helvetica); the same typeface in the same font size should be used for all figures in a paper. Use 'symbols' font for Greek letters. All display items should be on a white background, and should avoid excessive boxing, unnecessary colour, spurious decorative effects (such as three-dimensional 'skyscraper' histograms) and highly pixelated computer drawings. The vertical axis of histograms should not be truncated to exaggerate small differences. Labeling must be of sufficient size and contrast to be readable, even after appropriate reduction. The thinnest lines in the final figure should be no smaller than one point wide. Authors will see a proof that will include figures.

Figures divided into parts should be labeled with a lower-case bold a, b, and so on, in the same type size as used elsewhere in the figure. Lettering in figures should be in lower-case type, with only the first letter of each label capitalized. Units should have a single space between the number and the unit, and follow SI nomenclature (for example, ms rather than msec) or the nomenclature common to a particular field. Thousands should be separated by commas (1,000). Unusual units or abbreviations should be spelled out in full or defined in the legend. Scale bars should be used rather than magnification factors, with the length of the bar defined. In legends, please use verbal explanations such as "open red triangles" rather than visual queues.

Authors are encouraged to consider the needs of colourblind readers (a substantial minority of the male population) when choosing colours for figures. Many colourblind readers cannot interpret visuals that rely on discrimination of green and red, for example. Thus, we ask authors to recolor green-and-red heatmaps, graphs and schematics for which colours are chosen arbitrarily. Recoloring primary data, such as fluorescence or rainbow pseudo-coloured images, to colour-safe combinations such as green and magenta, turquoise and red, yellow and blue or other accessible colour palettes is strongly encouraged.

Provide figure files individually (Figure 1, Figure 2, Figure 3...etc.). Figure panels should be included in single file (Figures 1a-d should be included in Figure 1 file). Supply better quality main figure images only, (at least 300 dpi resolution) and that are readable and are in a widely openable file format (e.g. .ai, .eps, .pdf, .ps, .psd, .jpeg, .tiff, .png, .gif, .ppt, .pptx, .cdx.).

Figure legends

Figure legends begin with a brief title for the whole figure and continue with a short description of each panel and the symbols used, focusing on describing what is shown in the figure and de-emphasizing methodological details. The meaning of all error bars and how they were calculated should be described. 

Figures should be cited in the text in the order in which they appear. Each figure should be accompanied by a brief title that summarizes the whole figure and does not refer to specific panels. This should be followed by the figure legend 'body' that includes more in-depth details about the figure, limited to 350 words.

It is important that you define any new abbreviations, symbols or colors present in your figures in the associated legends. Do not use symbols in your legend, instead please write out the symbols in words (blue circles, red dashed line, etc.). Multi-panel figures should be presented on a single page and labeled using an a), b), c) convention and each panel should be described in the legend individually. Please note that this guidance also applies to any supplementary figures. Add the legends in the main manuscript file after references.

Tables

Please submit tables at the end of your text document (in Word or TeX/LaTeX, as appropriate). Tables that include statistical analysis of data should describe their standards of error analysis and ranges in a table legend.
 

Figures for peer review
 

At the initial submission stage authors should incorporate figures into the main article file, ensuring that any inserted figures are of sufficient quality to be clearly legible. If this is not possible in a combined manuscript file, authors should either submit separate high resolution figure files or deposit image data in a suitable repository (e.g. figshare) and use their option to provide a private sharing link for the referees to access it.
When submitting a final manuscript for publication, all figures must be uploaded as separate figure files ensuring that the image quality and formatting conforms to the specifications below.
 

Figures for publication
 

Each complete figure must be supplied as a separate file upload. Multi-part/panel figures must be prepared and arranged as a single image file (including all sub-parts; a, b, c, etc.). Please do not upload each panel individually.

Please read the digital images integrity and standards section of our editorial policies. When possible, we prefer to use original digital figures to ensure the highest-quality reproduction in the journal. For optimal results, prepare figures to fit A4 page-width. Figures that do not meet these standards will not reproduce well and publication may be delayed until we receive high-resolution images. We cannot offer to provide corrected reprints with higher image quality if only poor quality images were supplied at accept stage. The npj Series journal Editors reserve the right to make the final decision about matters of style and the size of figures.

When creating and submitting digital files, please follow the guidelines below. Failure to do so, or to adhere to the following guidelines, can significantly delay publication of your work.

Authors are responsible for obtaining permission to publish any figures or illustrations that are protected by copyright, including figures published elsewhere and pictures taken by professional photographers. The journal cannot publish images downloaded from the internet without appropriate permission.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

  • Provide images in RGB color and at 300 dpi or higher resolution.
  • Use the same typeface (Arial or Helvetica) for all figures. Use symbol font for Greek letters.
  • Use distinct colors with comparable visibility and avoid the use of red and green for contrast. Recoloring primary data, such as fluorescence images, to color-safe combinations such as green and magenta or other accessible color palettes is strongly encouraged. Use of the rainbow color scale should be avoided.
  • Figures are best prepared at the size you would expect them to appear in print. At this size, the optimum font size is 8pt.
  • We prefer vector files with editable layers. Acceptable formats are:  ai, .eps, .pdf, .ps and .svg for fully editable vector-based art; layered .psd and .tif for editable layered art; .psd, .tif, .png and .jpg for bitmap images; .ppt if fully editable and without styling effects; ChemDraw (.cdx) for chemical structures.
  • For reporting of new chemical structures, please refer to our Chemical Style Guide

If you would like to submit a suggestion for the featured image on our homepage with the final version of your manuscript, please also include the Image Licence to Publish form.
 

Submitting video files as figures

 

We encourage authors to submit videos as figures to support and showcase their research. Please consider the following guidelines when submitting videos:
  • Accepted file types include 3gp, asf, avi, flv, m1v, m2p, m2ts, m2v, m4a, m4v, mov, mp2, mp3, mp4, mpeg, mpg, mts, mxf, ogv, swf, wav, webm and wmv.
  • The maximum size of the video figure should be 150 MB. The combined file size for all content should be no larger than 1GB. 
  • Videos will be published online within your article text on our website and the first frame of your video will be used in the PDF file.
  • Please add the following sentence to the relevant figure caption in the manuscript file to identify video figures: 'In the PDF version of this article, please click anywhere on the figure or caption to play the video in a separate window.’
  • If authors wish to incorporate a video in a multipart figure, the whole figure would need to be submitted as a video. 
In addition, please follow our general guidelines on submitting figures, more information here.

 

Statistical guidelines
 

Comprehensive information on the statistical analyses used must be included in the paper. The Methods must include a statistics and reproducibility section with the following information. 

Every article that contains statistical testing should state the name of the statistical test, the n value for each statistical analysis, the comparisons of interest, a justification for the use of that test (including, for example, a discussion of the normality of the data when the test is appropriate only for normal data), the alpha level for all tests, whether the tests were one-tailed or two-tailed, and the actual P value for each test (not merely "significant" or "P < 0.05"). It should be clear what statistical test was used to generate every P value. Use of the word "significant" should always be accompanied by a P value; otherwise, use "substantial," "considerable," etc.

Data sets should be summarized with descriptive statistics, which should include the n value for each data set, a clearly labeled measure of centre (such as the mean or the median), and a clearly labeled measure of variability (such as standard deviation or range). Ranges are more appropriate than standard deviations or standard errors for small data sets. Graphs should include clearly labeled error bars. Authors must state whether a number that follows the ± sign is a standard error (s.e.m.) or a standard deviation (s.d.).

When plotting data, we require authors to use a format that clearly shows the full data distribution. If using a bar chart, please note that either individual data points must be overlaid on the bars or the chart must be converted to a dot-plot or box-and-whisker-plot format. 

Authors must justify the use of a particular test and explain whether their data conform to the assumptions of the tests. Three errors are particularly common:

Multiple comparisons: When making multiple statistical comparisons on a single data set, authors should explain how they adjusted the alpha level to avoid an inflated Type I error rate, or they should select statistical tests appropriate for multiple groups (such as ANOVA rather than a series of t-tests).

Normal distribution: Many statistical tests require that the data be approximately normally distributed; when using these tests, authors should explain how they tested their data for normality. If the data do not meet the assumptions of the test, then a non-parametric alternative should be used instead.

Small sample size: When the sample size is small (less than about 10), authors should use tests appropriate to small samples or justify their use of large-sample tests.

 

Gene nomenclature
 

Authors should use approved nomenclature for gene symbols, and use symbols rather than italicized full names (for example Ttn, not titin). Please consult the appropriate nomenclature databases for correct gene names and symbols. A useful resource is Entrez Gene, available from NCBI.

Approved human gene symbols are provided by HUGO Gene Nomenclature Committee (HGNC), e-mail: hgnc@genenames.org; see also www.genenames.org. Approved mouse symbols are provided by The Jackson Laboratory, e-mail: nomen@informatics.jax.org; see also www.informatics.jax.org/mgihome/nomen.

For proposed gene names that are not already approved, please submit the gene symbols to the appropriate nomenclature committees as soon as possible, as these must be deposited and approved before publication of an article.

Avoid listing multiple names of genes (or proteins) separated by a slash, as in 'Oct4/Pou5f1', as this is ambiguous (it could mean a ratio, a complex, alternative names or different subunits). Use one name throughout and include any others at first mention: 'Oct4 (also known as Pou5f1)'.

For information about referencing human single-nucleotide variants, see this editorial from Nature Genetics.
 

Characterisation of chemical and biomolecular materials
 

The npj Series journals are committed to publishing the highest-quality research. Manuscripts submitted to the journal will be held to rigorous standards with respect to experimental methods and characterization of compounds. Authors must provide adequate data to support their assignment of identity, purity and homogeneity for compounds and materials described in the manuscript. Editors and Reviewers will be responsible for assessing the completeness of the characterization. Authors should provide a statement confirming the source, identity and purity of known compounds and biomolecules that are central to the scientific study, even if they are purchased or resynthesised using published methods.
 

Chemical nomenclature and abbreviations

Molecular structures are identified by bold, Arabic numerals assigned in order of presentation in the text. Once identified in the main text or a figure, compounds may be referred to by their name preferably using systematic IUPAC nomenclature, by a defined standard abbreviation, or by the bold Arabic numeral (as long as the compound is referred to consistently as one of these three). Unconventional or specialist abbreviations should be defined at their first occurrence in the text.
 

Methods section

The Methods section should be written as concisely as possible but should contain all elements necessary to allow interpretation and replication of the results. We encourage the inclusion of specific sections for statistics, reagents and animal models. Experimental protocols that describe the synthesis of compounds must be included. Authors must describe the experimental protocol in detail, referring to amounts of each reagent in parentheses (e.g. 1.03 g, 0.100 mmol). The source for commercial compounds must be provided. Standard abbreviations for reagents and solvents are encouraged. Safety hazards posed by reagents or protocols must be identified clearly. Isolated mass and percent yields should be reported at the end of each protocol. Isomeric ratios of compounds obtained as an inseparable mixture must be quantified where possible. Authors are encouraged to share their step-by-step experimental protocols on a protocol sharing platform of their choice. protocols.io is a free-to-use and open resource for protocols. Protocols deposited in protocols.io are citable and can be linked from the published article. More details can be found at www.protocols.io
 

Chemical identity

Chemical identity for organic and organometallic compounds should be established through spectroscopic analysis. Detailed spectral data for compounds should be provided in list form (see below). Figures containing spectra generally will not be published as a manuscript figure unless the data are directly relevant to the central conclusions of the paper. Example format for compound characterization data:
mp: 100–102 °C (lit.ref 99–101 °C); [α]D = -21.5 (0.1 M in n-hexane); 1H NMR (400 MHz, CDCl3): δ 9.30 (s, 1H), 7.55–7.41 (m, 6H), 5.61 (d, J = 5.5 Hz, 1H), 5.40 (d, J = 5.5 Hz, 1H), 4.93 (m, 1H), 4.20 (q, J = 8.5 Hz, 2H), 2.11 (s, 3H), 1.25 (t, J = 8.5 Hz, 3H); 13C NMR (125 MHz, CDCl3): δ 165.4, 165.0, 140.5, 138.7, 131.5, 129.2, 118.6, 84.2, 75.8, 66.7, 37.9, 20.1; IR (Nujol): 1765 cm-1; UV/Vis: λmax 267 nm; HRMS (m/z): [M]+ calcd. for C20H15Cl2NO5, 420.0406; found, 420.0412; analysis (calcd., found for C20H15Cl2NO5): C (57.16, 57.22), H (3.60, 3.61), Cl (16.87, 16.88), N (3.33, 3.33), O (19.04, 19.09).
 

Yield and sample purity

Yield and evidence of sample purity is required for each isolated compound. Methods for purity analysis depend on the compound class. For most organic and organometallic compounds, purity may be demonstrated by high-field 1H NMR and 13C NMR data, although elemental analysis (±0.4%) is encouraged. Quantitative analytical methods including chromatographic (GC, HPLC, etc.) or electrophoretic analyses may be used to demonstrate purity for small molecules and polymeric materials. Melting points for crystalline compounds should be reported. In cases where isolation of pure samples is not possible (intermediates, mixtures, unstable species) or where the obtained quantities are not sufficient to perform a full characterization, a statement must be given, indicating that the species were not isolated or fully characterized.
 

Spectroscopy

Standard peak listings (see formatting guidelines above) for 1H NMR and proton-decoupled 13C NMR should be provided for organic compounds. Other NMR data should be reported (31P NMR, 19F NMR, etc.) when appropriate. Authors are encouraged to include high-quality images of spectra that cover the full range of chemical shifts scanned. Specific NMR assignments should be listed after integration values. Multidimensional NMR or decoupling experiments are encouraged when possible. UV or IR spectral data may be reported for the identification of characteristic functional groups, when appropriate.
 

Characterization of chiral compounds

The enantiomeric composition of chiral compounds should be characterized using appropriate techniques, including polarimetry, NMR, single crystal XRD, or by correlation of HPLC or GC. The specific rotation should be reported. Composition may be reported as enantiomeric excess or ratio.
 

Mass spectrometry

Authors should also provide mass spectral data to support molecular weight identity. High-resolution mass spectral (HRMS) data are preferred, and when m/z < 1,000, the calculated and found values should be within 0.003. When m/z > 1000, we expect an experimental value within 1 ppm of the calculated value.
 

Single-crystal X-ray diffraction

Crystalline solids may be characterized by single crystal XRD. Crystallography should be combined with other techniques as required to establish identity and purity. Manuscripts reporting new structures from crystallographic analysis should be accompanied by a standard crystallographic information file (.cif) and a structural figure with probability ellipsoids should be included in the main supplementary information file. The structure factors for each structure should also be submitted, preferably embedded in the main .cif file, although they may be provided as a separate .hkl and/or .fcf file. Use of the latest version of the program SHELXL, which embeds the structure factors information in the main .cif file, is encouraged. The structure factors and structural output must be checked using IUCr's CheckCIF routine and a PDF copy of the output included with the submission, explaining any A- or B-level alerts. Additionally, an explanation for all A- and B-level alerts must be given in the supplementary information. Crystallographic data for small molecules should be submitted to the Cambridge Structural Database and the deposition number referenced in the manuscript. Full access must be provided on publication. 
 

Solid state compounds

The homogeneity and purity of solid state compounds may be characterized by solid state NMR, powder X-ray diffraction data and where possible compared to calculated diffraction patterns.
 

Combinatorial compound libraries

Authors describing the preparation of combinatorial libraries should include standard characterization data for a diverse panel of library components.
 

Biomolecular identity

For new biopolymeric materials (oligosaccharides, peptides, nucleic acids, etc.), direct structural analysis by NMR spectroscopic methods may not be possible. In these cases, authors must provide evidence of identity based on sequence (when appropriate) and mass spectral characterization.
 

Biological constructs

Authors should provide sequencing or functional data that validates the identity of their biological constructs (plasmids, fusion proteins, site-directed mutants, etc.) either in the manuscript text, supplementary information, or the Methods section, as appropriate.
 

Chemical probe data

Manuscripts that report the identification and validation of new chemical probes are encouraged to submit their probes to the Chemical Probe Portal.
 

Small-molecule high-throughput screening data

Manuscripts reporting high-throughput screens of small-molecule libraries should include a supplementary table summarising the assay, library, screen and post-screen analysis. A template and instructions for preparing the high-throughput screening table are available.
 

Macromolecular structural data

Manuscripts reporting macromolecular structures should contain a table summarising structural and refinement statistics. Templates for such tables describing cryo-EM, NMR and X-ray crystallography data are available. To facilitate assessment of the quality of the structural data, a stereo image of a portion of the electron density map (for crystallography papers) or of the superimposed lowest energy structures (>10; for NMR papers) should be provided with the submitted manuscript. If the reported structure represents a novel overall fold, a stereo image of the entire structure (as a backbone trace) should also be provided. For cryo-EM structures, a representative micrograph showing individual particles should be provided in the submission. Crystallographic data for macromolecules must be submitted to the Worldwide Protein Data Bank (wwPDB), NMR data must be submitted to the Biological Magnetic Resonance Data Bank (BMRB) and cryo-EM data must be submitted to the Electron Microscopy Data Bank (EMDB). Deposition numbers must be referenced in the data availability statement in the manuscript. Full access must be provided on publication.
 

Microscopy

Microscopy images should be representative of the wider sample and labeled with scale bars. Full details for the reporting of microscopy experiments can be found on our policy page. 
 

Computational results

When electronic structure calculations are reported in the manuscript, the atomic coordinates of the optimised computational models should be provided. Codes and software should be available and properly referenced in the article and/or supplementary information. Input parameters, basis sets and coordinates of the input and output structures must be reported. If relative energies are reported, absolute energies should be provided in the supplementary information. For molecular dynamics trajectories, at least the initial and final configurations should be supplied. We encourage you to make them available by uploading the structures in any of the existing data repositories (see e.g. https://www.nature.com/sdata/policies/repositories). Alternatively, they can be supplied as a separate supplementary data file (ideally as a plain, unformatted text file).