Do Childhood Vaccines Have Non-Specific Effects on Mortality

A recent article by Kristensen et al. suggested that measles vaccine and bacille Calmette–Guérin (BCG) vaccine might\ud reduce mortality beyond what is expected simply from protection against measles and tuberculosis. Previous reviews of the potential effects of childhood vaccines on mortality have not considered methodological features of reviewed studies. Methodological considerations play an especially important role in observational assessments, in which selection factors for vaccination may be difficult to ascertain. We reviewed 782 English language articles on vaccines and childhood mortality and found only a few whose design met the criteria for methodological rigor. The data reviewed suggest that measles vaccine delivers its promised reduction in mortality, but there is insufficient evidence to suggest a mortality benefit above that caused by its effect on measles disease and its sequelae. Our review of the available data in the literature reinforces how difficult answering these considerations has been and how important study design will be in determining the effect of specific vaccines on all-cause mortality.\u

Public goods and decay in networks

We propose a simple behavioral model to analyze situations where (1) a group of agents repeatedly plays a public goods game within a network structure and (2) each agent only observes the past behavior of her neighbors, but is affected by the decisions of the whole group. The model assumes that agents are imperfect conditional cooperators, that they infer unobserved contributions assuming imperfect conditional cooperation by others, and that they have some degree of bounded rationality. We show that our model approximates quite accurately regularities derived from public goods game experiments

Optical Coherence Tomography May Be Used to Predict Visual Acuity in Patients with Macular Edema

Purpose. To determine whether the volume of retinal tissue passing between the inner and outer retina in macular edema could be used as an indicator of visual acuity. Methods. Diabetic and uveitic patients with cystoid macular edema (81 subjects, 129 eyes) were recruited. Best corrected logMAR visual acuity and spectral optical coherence tomography (OCT/SLO; OTI, Toronto, ONT, Canada) were performed in all patients. Coronal OCT scans obtained from a cross section of the retina between the plexiform layers were analyzed with a grid of five concentric radii (500, 1000, 1500, 2000, and 2500 μm centered on the fovea). The images were analyzed to determine the amount of retinal tissue present within each ring. A linear regression model was developed to determine the relationship between tissue integrity and logMAR visual acuity. Results. A linear relationship between tissue integrity and VA was demonstrated. The volume of retinal tissue between the plexiform layers in rings 1 and 2 (up to 1000 μm from the foveal center) predicted 80% of visual acuity. By contrast, central macular thickness within the central 1000 μm predicted only 14% of visual acuity. Conclusions. This study showed that the cross-sectional area of retinal tissue between the plexiform layers in cystoid macular edema, as imaged by OCT, is the best indicator of visual function at baseline. Further prospective treatment trials are needed to investigate this parameter as a predictor of visual outcome after intervention

The observation of slip bands in molybdenum single crystals by X-ray diffraction

The etch pit technique is a very simple method for the direct observation of dislocations and slip bands in single crystals. However, its use is often limited to certain crystallographic planes. For example, at present there is no report in the literature of an etchant which will reveal intersections on {112} planes of molybdenum. The Berg- Barrett X-ray micrography technique can be used to observe slip bands on a {112} plane. However, before using this method in studies of the growth of slip bands in molybdenum, it was deemed necessary to establish a correspondence between the X-ray contrast and the total slip band length (length of the trace containing dislocations associated with the slip band). To accomplish this goal X-ray topographs of slip bands were compared with the etch pit pattern produced by an electrolytic etchant developed by Das. These observations were made on a {124} surface of molybdenum (since the etchant does not reveal dislocation on a {112} surface)

Synchronization in small-world systems

We quantify the dynamical implications of the small-world phenomenon. We consider the generic synchronization of oscillator networks of arbitrary topology, and link the linear stability of the synchronous state to an algebraic condition of the Laplacian of the graph. We show numerically that the addition of random shortcuts produces improved network synchronizability. Further, we use a perturbation analysis to place the synchronization threshold in relation to the boundaries of the small-world region. Our results also show that small-worlds synchronize as efficiently as random graphs and hypercubes, and more so than standard constructive graphs

Beyond the island story? the opening ceremony of the London 2012 Olympic Games as public history

This paper evaluates the opening ceremony of the London 2012 Olympic Games as an exercise in public history. Public events have been widely identified within the study of nationalism as festivals that attempt to reinforce national identity and belonging. Contemporary Olympic Games figure in this literature as a specific form of event where the nature and content of a host state's identity is displayed for the global gaze of other nations. While opening ceremonies perform a rich display of national identity in any case, London 2012 is particularly significant for taking place at a time of major political contestation in the United Kingdom and has frequently been interpreted as an expression of radical patriotism. Traces of such patriotic thought associated particularly with England can be found in the opening ceremony's historical pageant and overall concept, showing resonances with the work of Raphael Samuel, who argued for a radical patriotism grounded in a multiplicity of accounts of the national past from many social positions. Depicting the nation through a multiplicity of biographical narratives produces a ‘mosaic' mode of representation which can be seen in other documentary and public history projects and in the political context of British public multiculturalism in the 2000s. This responds to the need for any national narrative to be composed through compressing the lives of millions of people into one coherent story, but complicates attempts to read a text such as the opening ceremony for what they ‘really' mean. A model for understanding narratives of the past as being produced in interaction between their initial creator(s) and their reader(s) is necessary for understanding not only the London 2012 opening ceremony in particular but public history and narratives of the national past in general

A blind HI survey of the M81 group

Results are presented of the first blind HI survey of the M81 group of galaxies. The data were taken as part of the HI Jodrell All Sky Survey (HIJASS). The survey reveals several new aspects to the complex morphology of the HI distribution in the group. All four of the known dwarf irregular (dIrr) galaxies close to M81 can be unambiguously seen in the HIJASS data. Each forms part of the complex tidal structure in the area. We suggest that at least three of these galaxies may have formed recently from the tidal debris in which they are embedded. The structure connecting M81 to NGC2976 is revealed as a single tidal bridge of mass approx. 2.1 x 10^8 Msol and projected spatial extent approx. 80 kpc. Two `spurs' of HI projecting from the M81 complex to lower declinations are traced over a considerably larger spatial and velocity extent than by previous surveys. The dwarf elliptical (dE) galaxies BK5N and Kar 64 lie at the spatial extremity of one of these features and appear to be associated with it. We suggest that these may be the remnants of dIrrs which has been stripped of gas and transmuted into dEs by close gravitational encounters with NGC3077. The nucleated dE galaxy Kar 61 is unambiguously detected in HI for the first time and has an HI mass of approx.10^8 Msol, further confirming it as a dE/dIrr transitional object. HIJASS has revealed one new possible group member, HIJASS J1021+6842. This object contains approx. 2 x 10^7 Msol of HI and lies approx.105arcmin from IC2574. It has no optical counterpart on the Digital Sky Survey.Comment: To be published in Astrophysical Journal Letters 9 pages, including 3 figure