The Worlds of UCL: teaching, learning and institutional histories

This article discusses an undergraduate module which introduces students to the study of the history of education through the lens of our own institutions – UCL (University College London, UK), founded in 1826, and the IOE (Institute of Education, UCL’s Faculty of Education and Society), founded in 1902. The module critically examines the close, but often hidden, connections between British education and empire, asking what impact these imperial legacies have today. After outlining the module’s origins and relationship with the history of UCL and the IOE, the article sets its creation in the wider context of initiatives that seek to critique and reimagine institutional histories within higher education for a variety of purposes. The article also explores the developing role of the IOE Archives team in teaching, and explores how academics and archivists work together to teach institutional histories, and how this work can prompt change

Category signaling and reputation

We propose that category membership can operate as a collective market signal for quality when low-quality producers face higher costs of gaining membership. The strength of membership as a collective signal increases with the sharpness of the category boundary, that is, contrast. Our empirical study focuses on biodynamic and organic viticulture in Alsace

Age-Related Structural Inertia: A Distance-based Approach

This paper proposes a distance-based characterization of age-related structural inertia as an increasing constraint on the speed of change as organizations age. Our framework regards organizations as points in multidimensional metric spaces of architectures. Organizational change means movement in this space. The speed of change is the ratio of the distance between positions in a space and the time it took for the organization to make the move. We illustrate how our distance-based approach can be used to formulate theories of age-related organizational inertia by using this representation to develop a model for a possible mechanism: age-related cultural resistance to change based on the dynamics of exposure of organizational members to architectural features. Our proposed mechanism is distinct from prevailing explanations and leads to new predictions. We also illustrate the value of our distance-based approach in a reanalysis of Sørensen and Stuart’s study of age variations in firms’ patenting behavior [Sørensen JB, Stuart TE (2000) Aging, obsolescence, and organizational innovation. Admin. Sci. Quart. 45(1):81–112]. On the basis of patent citations, we construct a space that allows us to characterize the positions of organizations and the speed at which they change. We find that organizational age has a negative effect on the speed of change

Snake neurotoxin α-bungarotoxin is an antagonist at native GABAA receptors

AbstractThe snake neurotoxin α-bungarotoxin (α-Bgtx) is a competitive antagonist at nicotinic acetylcholine receptors (nAChRs) and is widely used to study their function and cell-surface expression. Increasingly, α-Bgtx is also used as an imaging tool for fluorophore-labelling studies, and given the structural conservation within the pentameric ligand-gated ion channel family, we assessed whether α-Bgtx could bind to recombinant and native γ-aminobutyric type-A receptors (GABAARs). Applying fluorophore-linked α-Bgtx to recombinant αxβ1/2γ2 GABAARs expressed in HEK-293 cells enabled clear cell-surface labelling of α2β1/2γ2 contrasting with the weaker staining of α1/4β1/2γ2, and no labelling for α3/5/6β1/2γ2. The labelling of α2β2γ2 was abolished by bicuculline, a competitive antagonist at GABAARs, and by d-tubocurarine (d-Tc), which acts in a similar manner at nAChRs and GABAARs. Labelling by α-Bgtx was also reduced by GABA, suggesting that the GABA binding site at the receptor β–α subunit interface forms part of the α-Bgtx binding site. Using whole-cell recording, high concentrations of α-Bgtx (20 μM) inhibited GABA-activated currents at all αxβ2γ2 receptors examined, but at lower concentrations (5 μM), α-Bgtx was selective for α2β2γ2. Using α-Bgtx, at low concentrations, permitted the selective inhibition of α2 subunit-containing GABAARs in hippocampal dentate gyrus granule cells, reducing synaptic current amplitudes without affecting the GABA-mediated tonic current. In conclusion, α-Bgtx can act as an inhibitor at recombinant and native GABAARs and may be used as a selective tool to inhibit phasic but not tonic currents in the hippocampus

Semiparametric sieve-type generalized least squares inference

This article considers the problem of statistical inference in linear regression models with dependent errors. A sieve-type generalized least squares (GLS) procedure is proposed based on an autoregressive approximation to the generating mechanism of the errors. The asymptotic properties of the sieve-type GLS estimator are established under general conditions, including mixingale-type conditions as well as conditions which allow for long-range dependence in the stochastic regressors and/or the errors. A Monte Carlo study examines the finite-sample properties of the method for testing regression hypotheses

Evolution and chemical consequences of lightning-produced NOx observed in the North Atlantic upper troposphere

Airborne observations of NO during the Subsonics Assessment Ozone and Nitrogen Oxides Experiment (SONEX) reveal episodes of high NOx in the upper troposphere believed to be associated with lightning. Linkage to specific periods of lightning activity is possible through back trajectories and data from the National Lightning Detection Network. Lagrangian model calculations are used to explore the evolution of these high NOx plumes over the 1-2 days between their introduction and subsequent sampling by NASA's DC-8 aircraft. Simulations include expected changes in HNO3, H2O2, CH3OOH, HO2, and OH. Depending on the time of injection and dilution rate, initial NOx concentrations are estimated to range from 1 to 7 ppbv. Similar to many previous studies, simulated HNO3 concentrations tend to be greater than observations. Several possible explanations for this difference are explored. H2O2 observations are shown to be consistent with removal in convective activity. While it is possible that upper tropospheric CH3OOH is enhanced by convection, simulations show such increases in CH3OOH can be short-lived (e.g., < 12 hours) with no perceptible trace remaining at the time of sampling. High NO levels further prevent elevated levels of CH3OOH from propagating into increases in H2O2. HO2 is suppressed through reaction with NO in all cases. Simulated increases in OH exceeded a factor of 2 for some cases, but for the highest NOx levels, loss of OH via OH+NO2 offset production from HO2+NO. Additional increases in OH of 30-60% could result from convection of CH3OOH. A final point of discussion concerns how the chemistry within these plumes, their long-range transport, and their potential importance in sustaining background NOx far from source regions present a challenge to global and regional model simulations. Copyright 2000 by the American Geophysical Union

Locking plate fixation with and without inferomedial screws for proximal humeral fractures: a biomechanical study.

PURPOSE. To compare the efficacy of locking plate fixation with and without inferomedial screws in maintaining the reduction of a proximal humeral fracture. METHODS. 22 synthetic humerus models were used. A standardised 3-part proximal humeral fracture with a 4-mm wedge segment was created and fixed with a locking plate and screws with (n=11) and without (n=11) inferomedial screws. The intrafragmentary motion of the construct at 250, 500, 750, and 1000 cycles of 532 N loading, and the load to failure of the 2 groups were compared. RESULTS. Locking plate fixation with inferomedial screws reduced the mean intrafragmentary motion in all cycles (

CGP7930 - An allosteric modulator of GABABRs, GABAARs and inwardly-rectifying potassium channels

Type-A and -B GABA receptors (GABAARs/GABABRs) control brain function and behaviour by fine tuning neurotransmission. Over-time these receptors have become important therapeutic targets for treating neurodevelopmental and neuropsychiatric disorders. Several positive allosteric modulators (PAMs) of GABARs have reached the clinic and selective targeting of receptor subtypes is crucial. For GABABRs, CGP7930 is a widely used PAM for in vivo studies, but its full pharmacological profile has not yet been established. Here, we reveal that CGP7930 has multiple effects not only on GABABRs but also GABAARs, which for the latter involves potentiation of GABA currents, direct receptor activation, and also inhibition. Furthermore, at higher concentrations, CGP7930 also blocks G protein-coupled inwardly-rectifying K+ (GIRK) channels diminishing GABABR signalling in HEK 293 cells. In male and female rat hippocampal neuron cultures, CGP7930 allosteric effects on GABAARs caused prolonged rise and decay times and reduced the frequency of inhibitory postsynaptic currents and potentiated GABAAR-mediated tonic inhibition. Additional comparison between predominant synaptic- and extrasynaptic-isoforms of GABAAR indicated no evident subtype selectivity for CGP7930. In conclusion, our study of CGP7930 modulation of GABAARs, GABABRs and GIRK channels, indicates this compound is unsuitable for use as a specific GABABR PAM

Metalanguage in L1 English-speaking 12-year-olds: which aspects of writing do they talk about?

Traditional psycholinguistic approaches to metalinguistic awareness in L1 learners elicit responses containing metalanguage that demonstrates metalinguistic awareness of pre-determined aspects of language knowledge. This paper, which takes a more ethnographic approach, demonstrates how pupils are able to engage their own focus of metalanguage when reflecting on their everyday learning activities involving written language. What is equally significant is what their metalanguage choices reveal about their understanding and application of written language concepts