195 research outputs found
Fluctuations of the West Greenland Ice Sheet, independent ice caps and mountain glaciers during the twentieth century
The Greenland Ice Sheet contains enough water to raise global sea levels by ~7 metres, but predictions of the actual potential future contribution in a warming climate vary widely. These can be improved through a better understanding of how the whole ice sheet and its outlet glaciers have responded to past and present climate fluctuations. Recent studies have observed that Greenland Ice Sheet outlet glaciers have been retreating and thinning at increasingly faster rates since the 1990s. However, few studies have investigated the behaviour of the numerous independent ice caps that surround the ice sheet, or the land-terminating outlet glaciers. In addition, recent retreat is rarely put into context with long-term twentieth century fluctuations. This study has mapped ice sheet outlet glaciers and margins, independent ice cap outlets and mountain/valley glaciers at 11 time steps between the Little Ice Age and 2009 in northwest and southwest Greenland. Length changes of different glacier classes and terminus environments are examined, and overall glacier fluctuations compared to regional air temperatures and precipitation. Glaciers in the northwest have retreated further than those in the southwest at most time periods, with the exception of 1943/53-1964 when southwest glaciers underwent their most rapid rate of retreat. Length changes in both regions are driven by air temperature and precipitation changes. Tidewater outlet glaciers have generally retreated shorter distances than land-terminating glaciers in both absolute and relative terms over long time periods. These results imply that recent rapid retreat of many tidewater outlet glaciers in Greenland is not unprecedented, and may represent natural cyclical fluctuations rather than a long-term shift in behaviour. Ice sheet outlet glaciers have retreated shorter relative distances than independent ice caps and mountain/valley glaciers. Ice sheet margins advanced in the southwest between 1964 and 2001, and a slight advance of many independent glaciers was observed from ~1964-1987. It is unclear why this advance occurred. This study highlights the need for more research into the fluctuations of the independent ice caps and land-terminating glaciers in all regions of Greenland. In addition, more detailed research into the response of glaciers of all classes and terminus environments to climate change during the whole of the twentieth century is required to put recent changes into context
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Historical Sources of Science-as-Social-Practice: Michael Polanyi's Berlin
Historians and sociologists of science often identify the efflorescence of social stud ies of science with the work of postwar American intellectuals such as Robert K. Merton and Thomas S. Kuhn. They often also refer to the views of Michael Polanyi (1891-1976) on the roles of tacit knowledge, apprenticeship, social tradition, and intellectual dogmas (or what Kuhn popularized as "paradigms") in the construction of scientific knowledge. The roots of Polanyi's views on the social nature of sci ence and his insistence on the need for scientists' autonomy in managing their own affairs lie specifically in his career experiences as a physical chemist from 1920 to 1933 in the Kaiser-Wilhelm-Gesellschaft Institutes in Berlin-Dahlem. Polanyi worked in an institution in which scientific research was supported by an array of state, industrial, and philanthropic funds, but in which he and his colleagues enjoyed substantial autonomy in their everyday research. His own successes and failures in the fields of physical chemistry, x-ray crystallography, and solid-state chemistry led him to reflect upon the everyday practices of normal science and to stress the role of the ordinary rather than the revolutionary scientist in the production of scientific knowledge. Polanyi's views lend insight into the character of German science and the research institutes in Berlin-Dahlem in the late 19th and early 20th century.Keywords: Michael Polanyi, Kaiser-Wilhelm-Institute for Physical Chemistry, Scientific practice, German science, Thomas Kuhn, Scientific communit
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Aristocratic Culture and the Pursuit of Science : The De Broglies in Modern France
Louis de Broglie received the Nobel Prize in Physics in 1929 following experimental
confirmation of his theory of the wave properties of the electron. De Broglie was an
anomaly among twentieth-century physicists: he was a prince by birth who would become
the seventh duc de Broglie. What did it mean to be an aristocrat in an age of science? This
essay explores aristocratic culture in France in the early twentieth century and examines
the family life, education, scientific practices, and social values of Louis de Broglie, his
brother Maurice, who was a distinguished experimental physicist, and their sister Pauline,
who became a well-known novelist and literary scholar after her scientific interests were
discouraged.Copyrighted and originally published by the University of Chicago Press on behalf of the History of Science Society and can be found at: http://www.jstor.org/action/showPublication?journalCode=isi
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Scientific Biography: History of Science by Another Means?
Biography is one of the most popular categories of booksāand indeed the most popular
category among nonfiction books, according to one British poll. Thus, biography offers
historians of science an opportunity to reach a potentially broad audience. This essay
examines approaches typical of different genres of scientific biography, including historiansā
motivations in their choices of biographical subject and their decisions about strategies
for reconstruction of the biographical life. While historians of science often use
biography as a vehicle to analyze scientific processes and scientific culture, the most
compelling scientific biographies are ones that portray the ambitions, passions, disappointments,
and moral choices that characterize a scientistās life
Book Reviews
Creating a Local History Archive at Your Public Library. Faye Phillips.
Paper Cadavers: The Archives of Dictatorship in Guatemala. Kirsten Weld.
The Silence of the Archives. David Thomas, Simon Fowler, and Valerie Johnson.
The Bad-Ass Librarians of Timbuktu and Their Race to Save the World\u27s Most Precious Manuscripts. Joshua Hammer.
The International Business Archives Handbook: Understanding and Managing the Historical Records of Business. Edited by Alison Turton.
Putting Descriptive Standards to Work. Edited by Kris Kiesling and Christopher J. Prom.
Moving Image and Sound Collections for Archivists. Anthony Cocciolo
The Soft Power of Anglia: British Cold War Cultural Diplomacy in the USSR
This article contributes to the growing literature on the cultural Cold War through an exploration of the British national projection magazine Anglia, produced by the Foreign Office for distribution in the USSR from 1962 to 1992. As well as drawing attention to the significance of national magazines in general, the article sheds light on Britain's distinctive approach to propaganda and cultural diplomacy during the Cold War. It considers why the magazine was set up and endured for so long, despite considerable reservations about its value. It examines how Britain was projected in a manner that accorded with British understandings about the need for āsubtleā propaganda. Finally, it addresses the question of the magazine's impact in the USSR
Virology Experts in the Boundary Zone Between Science, Policy and the Public: A Biographical Analysis
This article aims to open up the biographical black box of three experts working in the boundary zone between science, policy and public debate. A biographical-narrative approach is used to analyse the roles played by the virologists Albert Osterhaus, Roel Coutinho and Jaap Goudsmit in policy and public debate. These figures were among the few leading virologists visibly active in the Netherlands during the revival of infectious diseases in the 1980s. Osterhaus and Coutinho in particular are still the key figures today, as demonstrated during the outbreak of novel influenza A (H1N1). This article studies the various political and communicative challenges and dilemmas encountered by these three virologists, and discusses the way in which, strategically or not, they handled those challenges and dilemmas during the various stages of the fieldās recent history. Important in this respect is their pursuit of a public role that is both effective and credible. We will conclude with a reflection on the H1N1 pandemic, and the historical and biographical ties between emerging governance arrangements and the experts involved in the development of such arrangements
Functional antibody and T-cell immunity following SARS-CoV-2 infection, including by variants of concern, in patients with cancer: the CAPTURE study
Patients with cancer have higher COVID-19 morbidity and mortality. Here we present the prospective CAPTURE study (NCT03226886) integrating longitudinal immune profiling with clinical annotation. Of 357 patients with cancer, 118 were SARS-CoV-2-positive, 94 were symptomatic and 2 patients died of COVID-19. In this cohort, 83% patients had S1-reactive antibodies, 82% had neutralizing antibodies against WT, whereas neutralizing antibody titers (NAbT) against the Alpha, Beta, and Delta variants were substantially reduced. Whereas S1-reactive antibody levels decreased in 13% of patients, NAbT remained stable up to 329 days. Patients also had detectable SARS-CoV-2-specific T cells and CD4+ responses correlating with S1-reactive antibody levels, although patients with hematological malignancies had impaired immune responses that were disease and treatment-specific, but presented compensatory cellular responses, further supported by clinical. Overall, these findings advance the understanding of the nature and duration of immune response to SARS-CoV-2 in patients with cancer
Late-Stage Metastatic Melanoma Emerges through a Diversity of Evolutionary Pathways
UNLABELLED: Understanding the evolutionary pathways to metastasis and resistance to immune-checkpoint inhibitors (ICI) in melanoma is critical for improving outcomes. Here, we present the most comprehensive intrapatient metastatic melanoma dataset assembled to date as part of the Posthumous Evaluation of Advanced Cancer Environment (PEACE) research autopsy program, including 222 exome sequencing, 493 panel-sequenced, 161 RNA sequencing, and 22 single-cell whole-genome sequencing samples from 14 ICI-treated patients. We observed frequent whole-genome doubling and widespread loss of heterozygosity, often involving antigen-presentation machinery. We found KIT extrachromosomal DNA may have contributed to the lack of response to KIT inhibitors of a KIT-driven melanoma. At the lesion-level, MYC amplifications were enriched in ICI nonresponders. Single-cell sequencing revealed polyclonal seeding of metastases originating from clones with different ploidy in one patient. Finally, we observed that brain metastases that diverged early in molecular evolution emerge late in disease. Overall, our study illustrates the diverse evolutionary landscape of advanced melanoma. SIGNIFICANCE: Despite treatment advances, melanoma remains a deadly disease at stage IV. Through research autopsy and dense sampling of metastases combined with extensive multiomic profiling, our study elucidates the many mechanisms that melanomas use to evade treatment and the immune system, whether through mutations, widespread copy-number alterations, or extrachromosomal DNA. See related commentary by Shain, p. 1294. This article is highlighted in the In This Issue feature, p. 1275
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