Caring for Weak Ties - the Natural History Museum as a Place of Encounter Between Amateur and Professional Science

This article is concerned with a community of practitioners that does not hold together well: amateur scientists. It examines the interrelationships between amateurs and professionals in a museum of natural history and focuses, in particular, upon two \'community-making devices\' through which they meet: an annual conference and a journal. I consider these devices as a place of encounter, or \'boundary encounter\', between amateurs and professionals. These encounters provide for a combination of several practices – practices of naming, assuring linguistic heterogeneity and thematic flexibility, exchanging knowledge and symbolic gifts – that enables the museum to keep the heterogeneous group of the amateurs somehow together. Since the connections between amateurs and professionals are not permanent, nor strong, but rather partial and fragile, they have therefore to be nurtured and cultivated with care. In fact, the museum and its professionals cannot continue to control – to use technical and \'cold\' devices to discipline subjects – but have to care by fostering a \'warm\' world of people. As I will show then, beyond their role as a place that brings together an epistemic collective, the encounters described in this paper also function as devices that nurture weak ties.Amateur Scientists, Weak Ties, Community-Making Devices, Boundary Encounters, Museum of Natural History, Epistemic Collective

Introduction: The Dynamics of Epistemic Communities

[No abstract][No keywords]

The Rise of the Knowledge Broker

International audienceKnowledge brokers are people or organizations that move knowledge around and create connections between researchers and their various audiences. This commentary reviews some of the literature on knowledge brokering and lays out some thoughts on how to analyze and theorize this practice. Discussing the invisibility and interstitiality of knowledge brokers, the author argues that social scientists need to analyze more thoroughly their practices, the brokering devices they use, and the benefits and drawbacks of their double peripherality. The author also argues that knowledge brokers do not only move knowledge, but they also produce a new kind of knowledge: brokered knowledge

On the boundaries and partial connections between amateurs and professionals

This paper explores the boundaries and partial connections between amateurs and professionals in the context of a museum of natural history. It examines how these boundaries are made and unmade, paying particular attention to their materiality and their heterogeneity. My aim is to draw the temporal, spatial and material profiles of amateurs and professionals. In doing so, the paper focuses on the partial connections between amateurs and professionals and shows that, in a sense, amateurs and professionals belong to more than one but less than many social spaces. I will further argue that professionalization and amateurisation are not merely historical processes, but also processes that happen in everyday practices in order to demarcate specific identities. While amateurs can be involved in co-producing science with professionals, they still might resist and avoid translation in order to protect their independence and concentrate their identity as amateur practitioners of science

The Reaction of SRL 202 Glass in J-13 and DIW

Static leach tests were performed in both 304L stainless steel and Teflon vessels using a synthetic high-level waste glass with either deionized water (DIW) or a tuff groundwater solution as the leachant to assess the effects of the vessel and the initial leachant composition on the extent and nature of the glass reaction. The tests were performed using monolith samples at 340 m{sup {minus}1} and crushed samplesat 2000 m{sup {minus}1} for times up to 1 year. The results show less silicon is released from the glass into the groundwater solution than into DIW at both high and low glass surface area/leachant volume ratios (SAN), but the alkali metal and boron releases are not affected by the leachant used. Tests performed in a stainless steel vessel resulted in slightly lower leachate pH values, but similar reaction rates to those performed in a Teflon vessel, as measured by the boron release. Blank tests with DIW or EJ-13 in the vessels showed the Teflon vessels to release small amounts of fluoride (1 to 2 ppm) and to acidify the DIW slightly (4.0 < pH < 5.6). The pH values of blank tests with EJ- 1 3 increased from 8.2 to about 8.6 in steel and to about 9.2 in Teflon vessels. The slightly higher pH values attained in Teflon vessels are attributed to outgassing of CO{sub 2} during the test

Impact of tunnel barrier strength on magnetoresistance in carbon nanotubes

We investigate magnetoresistance in spin valves involving CoPd-contacted carbon nanotubes. Both temperature and bias voltage dependence clearly indicate tunneling magnetoresistance as the origin. We show that this effect is significantly affected by the tunnel barrier strength, which appears to be one reason for the variation between devices previously detected in similar structures. Modeling the data by means of the scattering matrix approach, we find a non-trivial dependence of the magnetoresistance on the barrier strength. Furthermore, analysis of the spin precession observed in a nonlocal Hanle measurement yields a spin lifetime of $\tau_s = 1.1\,$ns, a value comparable with those found in silicon- or graphene-based spin valve devices.Comment: 10 pages, 5 figures, 1 tabl

Grammaire et topologie des anticipations

Science à la fois prometteuse et controversée, la biologie de synthèse est d’actualité scientifique et politique. Elle se situe au croisement de la biologie et de l’ingénierie, et se donne pour but de créer de nouvelles fonctions biologiques. Parmi les applications potentielles de la biologie de synthèse, on peut mentionner : les biocarburants fabriqués à partir d’algues, l’amélioration des médicaments et vaccins mais aussi la fabrication de biosenseurs pour détecter des espèces pathogènes ou..