Incidence of an Astronaut Not Sealing the Pressure Garment Visor on Reentry

Audiovisual records of a Project Mercury pilot’s activities during an orbital flight indicate that his visor was left open during reentry and descent to the sea surface, phases of flight during which cabin pressure loss was to be mitigated by suit pressurization; however, the suit could not have been pressurized with the visor open. Thus, for a presently unknown reason, a critical safety step—sealing the visor and making a pressure suit integrity test before reentry—was overlooked in this flight. Later, Space Shuttle flights were carried out with visors unsealed for much of the launch and landing phases, with the false assumption that they could be closed if the crew cabin were to lose cabin pressure rapidly. The lessons are clear: first, spaceflight crews should be trained to seal visors for the entire launch and landing phases; and second, procedure checklists will always be important to crewed flight, in both public and private spaceflight

Trauma: An Ideology in Search of Evidence and its Implications for the Social in Social Welfare

A recent special issue of this journal focussed on the emergence of the Adverse Childhood Experiences (ACEs) movement as a key driver of Scottish social policy. In this article, we extend the critiques advanced therein by locating ACEs within a wider cultural turn towards psychological trauma which, over the past decade, has become reified as a master theory across social welfare. Yet, the concept is insubstantial and ill-defined, and the claims made for policy based upon it are at best disputable. Its prominence is less evidence-based than it is testimony to how a particular (cultural and professional) ideology, regardless of its intellectual merit, can be insinuated into policy discourse. ACEs, we suggest, is utilised to provide the trauma paradigm with some ostensibly quantifiable substance. We illustrate our argument through reference to the Scottish Government’s National Trauma Training Programme (2020). We go on to consider some of the implications of such ideological capture for the direction of Scottish social welfare policy and practice. The prominence given to trauma perspectives has potentially iatrogenic consequences for those identified or self-identifying as traumatised. At a wider level, it reflects a professional and epistemic privileging of a narrow, ostensibly therapeutic, worldview which, in turn, acts to marginalise ‘the social’ that characterised erstwhile Scottish approaches to welfare

Kadison-Kastler stable factors

A conjecture of Kadison and Kastler from 1972 asks whether sufficiently close operator algebras in a natural uniform sense must be small unitary perturbations of one another. For n≥3 and a free, ergodic, probability measure-preserving action of SL<sub>n</sub>(Z) on a standard nonatomic probability space (X,μ), write M=(L<sup>∞</sup>(X,μ)⋊SL<sub>n</sub>(Z))⊗¯¯¯R, where R is the hyperfinite II1-factor. We show that whenever M is represented as a von Neumann algebra on some Hilbert space H and N⊆B(H) is sufficiently close to M, then there is a unitary u on H close to the identity operator with uMu∗=N. This provides the first nonamenable class of von Neumann algebras satisfying Kadison and Kastler’s conjecture. We also obtain stability results for crossed products L<sup>∞</sup>(X,μ)⋊Γ whenever the comparison map from the bounded to usual group cohomology vanishes in degree 2 for the module L<sup>2</sup>(X,μ). In this case, any von Neumann algebra sufficiently close to such a crossed product is necessarily isomorphic to it. In particular, this result applies when Γ is a free group

A remark on the similarity and perturbation problems

In this note we show that Kadison's similarity problem for C*-algebras is equivalent to a problem in perturbation theory: must close C*-algebras have close commutants?Comment: 6 Pages, minor typos fixed. C. R. Acad. Sci. Canada, to appea

Multispectral fingerprinting for improved in vivo cell dynamics analysis

Background: Tracing cell dynamics in the embryo becomes tremendously difficult when cell trajectories cross in space and time and tissue density obscure individual cell borders. Here, we used the chick neural crest (NC) as a model to test multicolor cell labeling and multispectral confocal imaging strategies to overcome these roadblocks. Results: We found that multicolor nuclear cell labeling and multispectral imaging led to improved resolution of in vivo NC cell identification by providing a unique spectral identity for each cell. NC cell spectral identity allowed for more accurate cell tracking and was consistent during short term time-lapse imaging sessions. Computer model simulations predicted significantly better object counting for increasing cell densities in 3-color compared to 1-color nuclear cell labeling. To better resolve cell contacts, we show that a combination of 2-color membrane and 1-color nuclear cell labeling dramatically improved the semi-automated analysis of NC cell interactions, yet preserved the ability to track cell movements. We also found channel versus lambda scanning of multicolor labeled embryos significantly reduced the time and effort of image acquisition and analysis of large 3D volume data sets. Conclusions: Our results reveal that multicolor cell labeling and multispectral imaging provide a cellular fingerprint that may uniquely determine a cell's position within the embryo. Together, these methods offer a spectral toolbox to resolve in vivo cell dynamics in unprecedented detail

What Will it Take to Make Solar Panels Cool?

With the predicted results of climate change looming, humanity must do all it can to limit greenhouse gas emissions. Maintaining a habitable environment along with the high quality of living associated with developed nations requires investment in renewable energy. Because national governments often fail to make responsible decisions for their country\u27s future, this burden falls to institutions like UMass Amherst. Although costly investments like solar panels substantially improve the sustainability of campus, some innovative improvements of existing solar energy infrastructure can go a long way. For example, when solar panels heat up they lose photovoltaic efficiency. We propose that UMass institute cooling systems on current and future solar panel structures. This may sound extravagant, but in this paper we outline a plan for a simple and affordable cooling system that can be constructed from supplies bought at a local hardware store. The University spent approximately $1.5 million dollars on the new solar canopy atop the Robsham’s Visitor Center. This structure generates an estimated$40,000 worth of electricity each year, with a 38 year return on investment. We expect a cooling system for each canopy to cost around $500 and to improve power output by more than 10 percent. This means that by the most conservative estimate, a$500 investment will generate an additional $4,000 worth of electricity, reducing the return on investment time by 4 years. Compared with the initial solar canopy investment, this magnitude of electricity generation would have cost$150,000. By comparison, $500 is peanuts. Read on to see how a little ingenuity can go a long way to save money and the environment

A classification of primitive permutation groups with finite stabilizers

We classify all infinite primitive permutation groups possessing a finite point stabilizer, thus extending the seminal Aschbacher-O'Nan-Scott Theorem to all primitive permutation groups with finite point stabilizers.Comment: Accepted in J. Algebra. Various changes, some due to the author, some due to suggestions from readers and others due to the comments of anonymous referee

The Extended Evolutionary Synthesis Facilitates Evolutionary Models of Culture Change

The Extended Evolutionary Synthesis (EES) is beginning to fulfill the whole promise of Darwinian insight through its extension of evolutionary understanding from the biological domain to include cultural information evolution. Several decades of important foundation-laying work took a social Darwinist approach and exhibited and ecologically-deterministic elements. This is not the case with more recent developments to the evolutionary study of culture, which emphasize non-Darwinian processes such as self-organization, potentiality, and epigenetic change.Comment: 19 pages, 1 figure, 3 tables; in Cliodynamics: The Journal of Quantitative History and Cultural Evolution, 9(2), 84-10