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Despite children’s unique vulnerability, clinical guidance and resources are lacking around the use of radiation medical countermeasures (MCMs) available commercially and in the Strategic National Stockpile to support immediate dispensing to pediatric populations. To better understand the current capabilities and shortfalls, a literature review and gap analysis were performed.
A comprehensive review of the medical literature, Food and Drug Administration (FDA)-approved labeling, FDA summary reviews, medical references, and educational resources related to pediatric radiation MCMs was performed from May 2016 to February 2017.
Fifteen gaps related to the use of radiation MCMs in children were identified. The need to address these gaps was prioritized based upon the potential to decrease morbidity and mortality, improve clinical management, strengthen caregiver education, and increase the relevant evidence base.
Key gaps exist in information to support the safe and successful use of MCMs in children during radiation emergencies; failure to address these gaps could have negative consequences for families and communities. There is a clear need for pediatric-specific guidance to ensure clinicians can appropriately identify, triage, and treat children who have been exposed to radiation, and for resources to ensure accurate communication about the safety and utility of radiation MCMs for children. (Disaster Med Public Health Preparedness. 2019;13:639-646)
Westgate Oxford is a commercial redevelopment of a large shopping complex in the center of Oxford, with clients Westgate Oxford Alliance and principal contractor Laing O'Rourke. The excavations, carried out by Oxford Archaeology, between 2014 and 2016, were required as part of UK Planning Guidelines and were the largest ever undertaken in the city and principally focused on a large medieval suburban friary. The project won Best Archaeological Project 2016 at the prestigious national British Archaeological Awards, and the outreach program, which included an evolving pop-up museum, was a significant contributing factor. This essay will demonstrate how to set up a pop-up museum in eight steps. The essay will look at how to work with different partners of a project. It will discuss choosing a story to tell and how to deal with a changing narrative on an archaeological site in “real time.” It will show how the Pop Up museum became the principal location for dissemination for the Westgate Oxford project. The essay will conclude with how to keep the story alive and plans for the future of the Westgate Oxford Pop Up Museum.
Preparing and responding to the needs of children during public health emergencies continues to be challenging. The purpose of this study was to assess the usefulness of a tabletop exercise in initiating pediatric preparedness strategies and assessing the impact of the exercise on participants’ understanding of and confidence in their roles during pediatric public health emergencies.
A tabletop exercise was developed to simulate a public health emergency scenario involving smallpox in a child, with subsequent spread to multiple states. During the exercise, participants discussed and developed communication, collaboration, and medical countermeasure strategies to enhance pediatric public health preparedness. Exercise evaluation was designed to assess participants’ knowledge gained and level of confidence surrounding pediatric public health emergencies.
In total, 22 participants identified over 100 communication and collaboration strategies to promote pediatric public health preparedness during the exercise and found that the most beneficial aspect during the exercise was the partnership between pediatricians and public health officials. Participants’ knowledge and level of confidence surrounding a pediatric public health emergency increased after the exercise.
The tabletop exercise was effective in identifying strategies to improve pediatric public health preparedness as well as enhancing participants’ knowledge and confidence surrounding a potential pediatric public health emergency. (Disaster Med Public Health Preparedness. 2018;12:582–586)
The generation of internal gravity waves by a vertically oscillating cylinder that is tilted to the horizontal in a stratified Boussinesq fluid of constant buoyancy frequency,
, is investigated. This variant of the widely studied horizontal configuration – where a cylinder aligned with a plane of constant gravitational potential induces four wave beams that emanate from the cylinder, forming a cross pattern known as the ‘St. Andrew’s Cross’ – brings out certain unique features of radiated internal waves from a line source tilted to the horizontal. Specifically, simple kinematic considerations reveal that for a cylinder inclined by a given angle
to the horizontal, there is a cutoff frequency,
, below which there is no longer a radiated wave field. Furthermore, three-dimensional effects due to the finite length of the cylinder, which are minor in the horizontal configuration, become a significant factor and eventually dominate the wave field as the cutoff frequency is approached; these results are confirmed by supporting laboratory experiments. The kinematic analysis, moreover, suggests a resonance phenomenon near the cutoff frequency as the group-velocity component perpendicular to the cylinder direction vanishes at cutoff; as a result, energy cannot be easily radiated away from the source, and nonlinear and viscous effects are likely to come into play. This scenario is examined by adapting the model for three-dimensional wave beams developed in Kataoka & Akylas (J. Fluid Mech., vol. 769, 2015, pp. 621–634) to the near-resonant wave field due to a tilted line source of large but finite length. According to this model, the combination of three-dimensional, nonlinear and viscous effects near cutoff triggers transfer of energy, through the action of Reynolds stresses, to a circulating horizontal mean flow. Experimental evidence of such an induced mean flow near cutoff is also presented.
Objectives: The Priorities and Evaluation Committee (PEC) funding recommendations for new cancer drugs in British Columbia, Canada have been based on both clinical and economic evidence. The British Columbia Ministry of Health makes funding decisions. We assessed the association between cost-effectiveness of cancer drugs considered from 1998 to 2008 and the subsequent funding decisions.
Methods: All proposals submitted to the PEC between 1998 and 2008 were reviewed, and the association between cost-effectiveness and funding decisions was examined by (i) using logistic regression to test the hypothesis that interventions with higher incremental cost-effectiveness ratios (ICERs) have a lower probability of receiving a positive funding decision and (ii) using parametric and nonparametric tests to determine if a statistically significant difference exists between the mean cost-effectiveness of funded versus not funded proposals. A sub-analysis was conducted to determine if the findings varied across different outcome measures.
Results: Of the 149 proposals reviewed, 78 reported cost-effectiveness using various outcome measures. In the proposals that used life-years gained as the outcome (n = 22), a statistically significant difference of nearly $115,000 was observed between the mean ICERs for funded proposals ($42,006) and for unfunded proposals ($156,967). An odds ratio indicating higher ICERs have a lower probability of being funded was also found to be statistically significant (p < .05).
Conclusions: Economic evidence appears to play a role in British Columbia cancer funding decisions from 1998 to 2008; other decision-making criteria may also have an important role in recommendations and subsequent funding decisions.
The idea that there may be a cut-off in the distribution of quasars at high redshifts (z∼4) has been of some recent interest through the work of Osmer (1982). The observation of such an epoch of quasar creation is potentially of great importance in relation to theories of galaxy formation, but the evidence from optically-selected quasar samples remains uncertain: quite apart from the notorious problems in achieving quantifiable completeness in objective-prism surveys, any observed lack of high-redshift quasars may always be attributed to absorption either by a neutral IGM or by dust in intervening galaxies. Radio-selected samples, however, do not suffer from these problems, and this paper aims to review what studies of extragalactic radio sources can tell us about the numbers of objects at the highest redshifts.
We consider the statistical testing of models for galaxy formation against the observed peculiar velocities on 10–100 Mpc scales (the Rubin-Ford effect). If we assume that observers are likely to be sited near maxima in the primordial field of density perturbations (Peacock & Heavens 1985: MNRAS 217, 805; Bardeen et al. 1986: Ap. J. 304, 15), then the observed filtered velocity field will be biased to low values by comparison with a point selected at random. The streaming-velocity data constrain models for galaxy formation with large-scale damping (adiabatic perturbations) to have a damping length close to the Rubin-Ford scale (rD ∼ 20 h−1 Mpc) and are mildly non-linear (Ω0.6 σo ∼1), where σo is the current fractional rms density variation. The Figure illustrates the regions of parameter space allowed at the 10,5,1 & 0.1% levels; the results are nearly independent of n, the power index of the primordial spectrum. Thus, both purely baryonic universes and universes dominated by massive neutrinos can account for the observed velocities, provided 0.1 ≲ Ω ≲ 1. In particular, the canonical Ω = 1 massive-neutrino model yields the required velocities quite naturally (in contradiction to the conclusion of Vittorio et al. 1986: Nature 323, 132), while not violating the constraints on the isotropy of the microwave background. For further details of this work, see Peacock, Lumsden & Heavens 1987: MNRAS in press.
We have calculated the growth of angular momentum about local density maxima at early epochs. We find that high peaks experience higher torques than low peaks, counteracting the short collapse time during which the high peaks can acquire angular momentum. Which effect is dominant depends on the perturbation power spectrum: for power spectra characteristic of both cold dark matter and hot dark matter, the effects nearly cancel, and the total angular momentum acquired by a collapsing object is almost independent of the height of the peak. Furthermore, the distributions of angular momenta acquired by collapsing protosystems are extremely broad, for all power spectra, far exceeding any modest differences between peaks of different height.
These results indicate that it is not possible to account for the systematic differences in angular momentum properties of disk and elliptical galaxies simply by postulating that the latter arise from fluctuations of greater overdensity, contrary to some recent suggestions. The figure shows the probability distributions for the final angular momentum acquired by peaks of dimensionless height 1–4, for a power spectrum similar to cold dark matter. A fuller account of this work has been submitted to MNRAS.
We are working on an all-sky sample of radio-selected elliptical galaxies to provide a powerful probe of clustering & streaming velocities on 10–100 Mpc scales. Our eventual sample will have the limits (i) S>0.5 Jy at 1.4 GHz; (ii) 0.01<z<0.1; (iii) |b| >15°; about 400 galaxies satisfy these criteria. We are pursuing an optical programme to obtain (i) B & I CCD frames for all galaxies; (ii) spectra for the galaxies without accurate redshifts; this is now about 30% complete. Accurate optical luminosity indicators exist for radio galaxies, without needing to measure velocity dispersions (using the correlations with optical core radius and radio central-component luminosity: Hoessel 1980: Ap. J. 241, 493; Fabbiano et al. 1984: Ap. J. 277, 115). We therefore expect to provide an accurate test of the Rubin-Ford effect, and to extend such studies to higher redshift. We also have a preliminary result for the 3D two-point correlation function of radio galaxies (see Figure). This strong clustering signal is seen only from galaxies in the decade of radio power below the Fanaroff-Riley division. These objects are known a priori to lie in cluster environments of average Abell richness 0 (Longair & Seldner 1979: MNRAS 189, 433). This result therefore provides confirmation of a trend of clustering with richness independent of optical selection effects in choosing a cluster sample.
The 2dF Galaxy Redshift Survey is now complete, and the full data are public. 2dFGRS was the first survey to observe more than 100,000 redshifts, making possible precise measurements of many aspects of galaxy clustering, which can be studied as a function of galaxy spectral type, and also of broad-band colour. Early-type galaxies are more strongly clustered than late types, with a relative bias of b = 1.25 ± 0.09 on large scales. For both types, luminosity dependence of clustering is detected at high significance, and is well described by a relative bias of b/b* = 0.85 + 0.15(L/L*). This is consistent with the observation that L* in rich clusters is brighter than the global value by 0.28 ± 0.08 mag. Redshift-space distortions from large-scale infall velocities measure the distortion parameter β = Ω0.6m/b = 0.49 ± 0.09. The power spectrum is measured to ≲ 10% accuracy for k > 0.02 h Mpc--1, and is well fitted by a CDM model with Ωmh = 0.18 ± 0.02 and a baryon fraction of 0.17 ± 0.06. The 2dFGRS plays an essential role in breaking model degeneracies inherent in CMB data; a joint analysis with WMAP results requires Ωm = 0.25 ± 15% and h = 0.73 ± 5%, assuming scalar fluctuations.
Increased marine 14C reservoir ages from the surface water of the North Atlantic are documented for the Younger Dryas period. We use terrestrial and marine AMS 14C dates from the time of deposition of the Icelandic Vedde Ash to examine the marine 14C reservoir age. This changed from its modem North Atlantic value of ca. 400 yr to ca. 700 yr during the Younger Dryas climatic event. The increased marine reservoir age has implications for both comparing climatic time series dated by 14C and understanding palaeoceanographic changes that generated the increase.
The main tools describing the formation of large-scale structure are reviewed. Detailed emphasis is given to the Cold Dark Matter model, since this appears to be a close match to observation. A consistent normalization that satisfies both CMB constraints and the cluster abundance requires Ωm ⋍ 0.35 for a flat universe and scale-invariant fluctuations. Discrepancies between observed galaxy power spectra and CDM predictions are discussed; a heuristic model for galaxy bias is proposed that potentially allows such scale-dependent bias to be understood.
The study of radio galaxies selected at mJy flux levels has the potential to resolve two important issues in observational cosmology provided redshifts can be determined or reliably estimated for complete samples of such sources. First, the deep flux limit, combined with the shape of the radio luminosity function means that the redshift distribution of such samples provides a much more powerful test of the existence of a high-redshift cutoff for radio sources (Dunlop & Peacock 1990) than can be provided by further studies of brighter radio samples. Second, as a consequence of selection from bright radio surveys, the detailed study of galaxies at z > 2 has to date been confined to objects of extreme radio power (e.g. 4C41.17, Chambers et al. 1990; B2 0902+34, Eales et al. 1993), and it has now become clear that the ultraviolet-infrared properties of such sources are strongly contaminated by processes connected to the AGN (Eales & Rawlings 1993; Dunlop & Peacock 1993). Being 100-1000 times less radio luminous than these extreme sources, mJy radio galaxies at comparable redshifts should provide much more representative probes of the formation and evolution of elliptical galaxies in general.
The fields of research covered by Division VIII and its two Commissions have experienced remarkable progress over the last several years. This is due at least in part to the proliferation of major new observational facilities, and the addition of the several 8-m class telescopes presently being completed and new space facilities which will have a huge impact in the years to come. Many of the important recent scientific developments are summarized on the following pages in the reports of Commission 28 and Commission 47. These reports have been prepared in the “short” form, and are intended both to present the major scientific highlights and the most important conference proceedings and reviews for further reading.
Cosmology is one of the most dynamically evolving areas of astrophysics today. Twenty years ago the estimates of the amplitude of the primordial fluctuations were about 10-3, almost a factor of 100 off of today’s measurements. Ten years ago we could only hope for high precision measurements of large scale structure, there were less than 5000 redshifts measured, and only a handful of normal galaxies with z > 1 were known. Computer models of structure formation had just begun to consider non-power-law spectra based on physical models like hot/cold dark matter. As a consequence there was considerable freedom in adjusting parameters in the various galaxy formation scenarios. In contrast, many of today’s debates are about factors of 2 and soon we will be arguing about 10% differences. The Harrison-Zeldovich shape of the primordial fluctuation spectrum, first derived from philosophical arguments can now be quantified from detections of fluctuations by COBE. The number of available redshifts is beyond 50,000, and soon we will have redshift surveys surpassing 1 million galaxies. N-body simulations are becoming more sophisticated, of higher resolution, and incorporating complex gas dynamics.
Digital stacking of Schmidt Plates greatly increases the depth of the data allowing detection of galaxies at ∼ 1. We can probe the angular correlations of galaxy and cluster positions over scales of ∼ 500h−1 Mpc. Radial distance information can be obtained by identifying radio galaxies in the field and using their “standard candle” properties. A search for cosmic string effects, beginning with the stacked dataset, has now been extended to ∼ 100 equatorial J-plates.
The Joint European X-Ray Telescope, JET-X, is one of the core instruments of the scientific payload of the USSR SPECTRUM-X astrophysics mission due for launch in 1993. The JET-X instrument concept is described and its scientific performance and capability discussed.
Given the ubiquity of layering in environmental stratifications, an interesting example being double-diffusive staircase structures in the Arctic Ocean, we present the results of a joint theoretical and laboratory experimental study investigating the impact of multiple layering on internal wave propagation. We first present results for a simplified model that demonstrates the non-trivial impact of multiple layering. Thereafter, utilizing a weakly viscous linear model that can handle arbitrary vertical stratifications, we perform a comparison of theory with experiments. We conclude by applying this model to a case study of a staircase stratification profile obtained from the Arctic Ocean, finding a rich landscape of transmission behaviour.