592 research outputs found
External fluctuations in front dynamics with inertia: The overdamped limit
We study the dynamics of fronts when both inertial effects and external
fluctuations are taken into account. Stochastic fluctuations are introduced as
multiplicative noise arising from a control parameter of the system. Contrary
to the non-inertial (overdamped) case, we find that important features of the
system, such as the velocity selection picture, are not modified by the noise.
We then compute the overdamped limit of the underdamped dynamics in a more
careful way, finding that it does not exhibit any effect of noise either. Our
result poses the question as to whether or not external noise sources can be
measured in physical systems of this kind.Comment: 4 pages, 1 figure, accepted for publication in European Physical
Journal
Academic and Molecular Matrices:A Study of the Transformations of Connective Tissue Research at the University of Manchester (1947–1996)
This paper explores the different identities adopted by connective tissue research at the University of Manchester during the second half of the 20th century. By looking at the long-term redefinition of a research programme, it sheds new light on the interactions between different and conflicting levels in the study of biomedicine, such as the local and the global, or the medical and the biological. It also addresses the gap in the literature between the first biomedical complexes after World War II and the emergence of biotechnology. Connective tissue research in Manchester emerged as a field focused on new treatments for rheumatic diseases. During the 1950s and 60s, it absorbed a number of laboratory techniques from biology, namely cell culture and electron microscopy. The transformations in scientific policy during the late 70s and the migration of Manchester researchers to the US led them to adopt recombinant DNA methods, which were borrowed from human genetics. This resulted in the emergence of cell matrix biology, a new field which had one of its reference centres in Manchester. The Manchester story shows the potential of detailed and chronologically wide local studies of patterns of work to understand the mechanisms by which new biomedical tools and institutions interact with long-standing problems and existing affiliations
Design and Implementation of a Decision Support System for Analysing Ranking Auction Markets for Internet Search Services
Mapping and sequencing information: the social context for the genomics revolution
In 1983, after devoting some eight years of his life to the
description of how a nematode worm develops from an
embryo into an adult, molecular biologist John Sulston
embarked on a remarkably different project: he decided
to map the worm’s genome. Sulston’s impulsive desire
to characterise this creature’s DNA from start to finish
offers only a partial explanation for this transition.
Instead, a close examination of the wider social context
for this ‘moment’ in molecular biology gives a more
rewarding explanation of Sulston’s intellectual leap.
This reveals a world in which biotechnology gradually
adapted to and integrated into an ‘information society’
increasingly dependent on the creation, distribution and
manipulation of information. The application of computing
to DNA during the first half of the 1980s was crucial
for this integration, fostering the emergence of genomics
and ultimately the Human Genome Project.This research was conducted while holding postgraduate fellowships given by Caja Madrid Foundation, Madrid City Hall and Residencia de Estudiantes (Spain), as well as a Hans Rausing Fellowship given by the Centre for the History of Science, Imperial College, London. Without them, it would not have been feasible.Peer reviewe
The Rise and Fall of the Idea of Genetic Information (1948-2006)
[ES] El 26 de junio de 2000, durante la presentación del primer borrador del Proyecto Genoma Humano, el entonces presidente de los Estados Unidos, Bill Clinton, afirmó que "hoy estamos aprendiendo el lenguaje en el que Dios creó la vida". Detrás de sus palabras se escondía una historia de más de medio siglo basada en el entendimiento del ADN como información. Mi artículo analiza esta historia, abordando los orígenes de la visión informacional de nuestros genes a principios de los 50, cómo esta visión afectó las investigaciones en el código genético (años 50 y 60) y la transformación de la idea de información genética en el contexto de las primeras técnicas de secuenciación de ADN y de la bioinformática (años 80 y 90). Propongo que el concepto de ADN como información alcanzó un climax con el planteamiento del Proyecto Genoma Humano, pero actualmente afronta una crisis que coincide con el cuestionamiento de la idea de sociedad de la información. Finalmente, analizo el desarrollo de la biología de sistemas como paradigma alternativo.[EN] On 26 June 2000, during the presentation of the Human Genome Project’s first draft,
Bill Clinton, then President of the United States, claimed that “today we are learning
the language in which God created life”.1 Behind his remarks lay a story of more than
half a century involving the understanding of DNA as information. This paper analyses
that story, discussing the origins of the informational view of our genes during the
early 1950s, how such a view affected the research on the genetic code (1950s and
‘60s) and the transformation of the information idea in the context of DNA sequencing
and bioinformatics (‘80s and ‘90s). I suggest that the concept of DNA as information
reached a climax with the proposal of the Human Genome Project (HGP), but is
currently facing a crisis coinciding with the questioning of the information society.
Finally, I discuss the emergence of systems biology as an alternative paradigm.This research was conducted while holding postgraduate fellowships given by Caja
Madrid Foundation, Madrid City Hall and Residencia de Estudiantes (Spain) as well as
a Hans Rausing Fellowship given by the Centre for the History of Science, Imperial
College, London. Without them, it would not have been feasible.Peer reviewe
From the Genetic to the Computer Program:The Historicity of 'Data' and 'Computation' in the Investigations on the Nematode Worm<em> C. elegans</em> (1963-1998)
The proactive historian:Methodological opportunities presented by the new archives documenting genomics
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