The end of an era.

These volumes conclude a series initiated in 1974, marking almost fifty years of effort by a huge cohort of scholars. This review is thus a valedictory for the whole series as well as an account of what we have learned from the most recent volumes about Darwin's final years (1879-82). The project was begun by Frederick Burckhardt, who shared the editorial role for the early volumes with Sydney Smith and a rolling sequence of assistant editors and advisers who eventually comprised a significant fraction of the leading members of what used to be called the 'Darwin industry'. Smith passed away in 1988 (volume 7 notes his legacy). Burkardt too left this world in 2007 - volume 16, part 1 includes an obituary, but his name has been retained and Cambridge University Press still ask that the series be cited as 'Burkhardt et al.' Duncan Porter took over for volumes 8-15, again with a sequence of fellow editors and assistants, after which James Secord became head of the project through its final years. The dedications of successive volumes record the efforts of individual scholars who have aided the teams and the involvement of the many institutions and foundations that have leant moral and material support over the years. For those of us with Cambridge connections, the University Library will not seem the same without the presence of the team it supported.

A revolutionary joins the establishment: Reproductive Biomedicine Online turns 20.

This commentary highlights the publishing revolution achieved by Robert Edwards in founding Reproductive Biomedicine Online. It corrects some inaccuracies in the account given by Roger Gosden in his recently published book Let There Be Life: An Intimate Portrait of Robert Edwards and His IVF Revolution.

A century of Hereditas: from local publication to international journal.

BACKGROUND: The Mendelian Society of Lund launched Hereditas in 1920. The purpose of this article is to give an overview of Hereditas's hundred-year existence, focusing on the conditions for a learned society to publish a scientific journal, and the journal's importance for the publication and dissemination of genetic research. The article focuses on the historical development of the journal and analyses how the content and orientation of research published in Hereditas have changed over the years. METHODS: The historical study is based on the collation and interpretation of archival material, mainly held in the Mendelian Society's archive, which includes the Hereditas archive. The bibliometric analyses are based on bibliographic metadata from Web of Science (WoS). Together with descriptive statistics, co-citation analyses were performed by using BibExcel, in combination with the clustering and visualisation tool VOSviewer. Journals with articles citing Hereditas articles were identified as a complement to the co-citation analyses. RESULTS: The history of the journal falls into three main periods: a local period, 1920-1959, when Hereditas was primarily intended for Swedish geneticists; a Scandinavian period, 1960-1988, when Hereditas was the official journal of the Scandinavian Association of Geneticists; and an international period from 1989 onwards. The original decision that Hereditas should cover genetic research with no particular specialisation was retained throughout. Its publications demonstrate the continuing presence of genetic research on plants and animals, albeit with a shifting focus, while human genetics emerged slowly and reached its peak in the period 1960-1988. CONCLUSION: In the hundred years of Hereditas's existence, the publishing landscape has changed dramatically, including a far greater number of specialist journals, changes to the academic merit system, new commercial models for publishing, and digitalisation. Over the years, the journal's survival has therefore been dependent on the strong commitment of its owners and an ability to adapt to changing conditions.

C. Barber Mueller: appreciation.

This commentary was written in memory of C. Barber Mueller, who died at age 97 on Feb. 13, 2014. He was co-editor in chief of CJS from 1972 to 1992.

The development of drug metabolism research as expressed in the publications of ASPET: part 1, 1909-1958.

This is the first of three articles covering the development of drug metabolism research in the United States during the first 100 years of the American Society for Pharmacology and Experimental Therapeutics (ASPET). Before 1909, the majority of drug metabolism research was performed in Europe. The period from 1909 to 1958 saw extensive development of the methods required for modern metabolism studies. Examples of trends and specific discoveries are drawn from the archives of ASPET publications.

Mapping the knowledge structure of frailty in journal articles by text network analysis.

BACKGROUNDS: This study was to understand the trends of frailty research and networking features of keywords from the academic articles focusing on frailty in the last four decades. METHOD: Keywords were extracted from articles (n = 6,424) retrieved from Web of Science, from 1981 to April 2016, using Bibexcel, and a social network analysis was conducted using Net Miner. RESULTS: The core-keywords of research on frailty are constantly changing over the last 40 years. The keywords were tended to focus on impact in the 1980s, and moved to the determinants (i.e., malnutrition) in the 1990s and the 2000s, and in the 2010s, most of keywords were about determinants and measurement of frailty. In the early stages of frailty research, individual behaviour modifications were emphasized as intervention. Keywords with the highest degree centralities were 'impact' (1980s), 'frailty' (1990s), 'home care' (2000s), and 'dementia' (2010s). Keywords with the highest betweenness centralities were 'model' (1980s), 'frailty' (1990s), 'chronic disease' (2000s), and 'malnutrition' (2010s). DISCUSSION: This study provides a systematic overview of frailty knowledge development. 'Dementia' was found to be the keyword with the highest degree centrality, showing that studies on cognitive function are those being most actively conducted in recent decade. In the 2000s frailty research, sub-themes were sarcopenia, dementia and disability, indicating that frailty was investigated from the view of disease. In the 2010s, obesity, nutrition, prevention, evaluation, and ADL (activities of daily living) were sub-themes of the research network that focused on frailty prevention.