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Inappropriate antibiotic use is associated with increased antimicrobial resistance and adverse events that can lead to further downstream patient harm. Preventative strategies must be employed to improve antibiotic use while reducing avoidable harm. We use the term “antibiotic never events” to globally recognize and define the most inappropriate antibiotic use.
Innovation platforms are fast becoming part of the mantra of agricultural research for development projects and programmes. Their basic tenet is that stakeholders depend on one another to achieve agricultural development outcomes, and hence need a space where they can learn, negotiate and coordinate to overcome challenges and capture opportunities through a facilitated innovation process. Although much has been written on how to implement and facilitate innovation platforms efficiently, few studies support ex-ante appraisal of when and for what purpose innovation platforms provide an appropriate mechanism for achieving development outcomes, and what kinds of human and financial resource investments and enabling environments are required. Without these insights, innovation platforms run the risk of being promoted as a panacea for all problems in the agricultural sector. This study makes clear that not all constraints will require innovation platforms and, if there is a simpler and cheaper alternative, that should be considered first. Based on the review of critical design principles and plausible outcomes of innovation platforms, this study provides a decision support tool for research, development and funding agencies that can enhance more critical thinking about the purposes and conditions under which innovation platforms can contribute to achieving agricultural development outcomes.
We identify the longest expansion in U.S. history, a recession-free 16-year period from 1841 to 1856 that we call America's First Great Moderation. Using newer data on industrial production, we show that the record-long expansion was primarily driven by a boom in transportation-goods investment following the discovery of gold in California. Furthermore, the low volatility of industrial production and stock returns during the First Great Moderation, which occurred during a period without a U.S. central bank, is similar to that observed for the Second Great Moderation (1984–2007).
The Taipan galaxy survey (hereafter simply ‘Taipan’) is a multi-object spectroscopic survey starting in 2017 that will cover 2π steradians over the southern sky (δ ≲ 10°, |b| ≳ 10°), and obtain optical spectra for about two million galaxies out to z < 0.4. Taipan will use the newly refurbished 1.2-m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument, which includes an innovative ‘Starbugs’ positioning system capable of rapidly and simultaneously deploying up to 150 spectroscopic fibres (and up to 300 with a proposed upgrade) over the 6° diameter focal plane, and a purpose-built spectrograph operating in the range from 370 to 870 nm with resolving power R ≳ 2000. The main scientific goals of Taipan are (i) to measure the distance scale of the Universe (primarily governed by the local expansion rate, H0) to 1% precision, and the growth rate of structure to 5%; (ii) to make the most extensive map yet constructed of the total mass distribution and motions in the local Universe, using peculiar velocities based on improved Fundamental Plane distances, which will enable sensitive tests of gravitational physics; and (iii) to deliver a legacy sample of low-redshift galaxies as a unique laboratory for studying galaxy evolution as a function of dark matter halo and stellar mass and environment. The final survey, which will be completed within 5 yrs, will consist of a complete magnitude-limited sample (i ⩽ 17) of about 1.2 × 106 galaxies supplemented by an extension to higher redshifts and fainter magnitudes (i ⩽ 18.1) of a luminous red galaxy sample of about 0.8 × 106 galaxies. Observations and data processing will be carried out remotely and in a fully automated way, using a purpose-built automated ‘virtual observer’ software and an automated data reduction pipeline. The Taipan survey is deliberately designed to maximise its legacy value by complementing and enhancing current and planned surveys of the southern sky at wavelengths from the optical to the radio; it will become the primary redshift and optical spectroscopic reference catalogue for the local extragalactic Universe in the southern sky for the coming decade.
To determine the effectiveness of glacial erosion and the magnitude of cosmogenic nuclide inheritance from prior periods of cosmic-ray exposure, we measured the abundance of 10Be and 26Al in nine samples collected from bedrock, boulders and cobbles exposed by the retreat of Tumbling Glacier, Baffin Island, Canada. Most samples had nuclide concentrations so low that we were only able to set upper limits for nuclide abundance. Three boulders, two on a Neoglacial moraine of Tumbling Glacier that impounds Crater Lake and one on a roche moutonnée within the Neoglacial moraine loop, had nuclide abundances indicating no more than 900 yr of exposure at the surface. Three bedrock samples, striated by Tumbling Glacier and exposed by ice retreat within the last 20 yr, have similarly low nuclide abundances. One bedrock sample, covered by Tumbling Glacier ice for some part of the Holocene but not eroded, allows us to estimate crudely the duration of Neoglaciation at our sample site (about 5450 yr) and to provide a lower limit on the erosion rate of Tumbling Glacier (0.10 ± 0.03 mm a–1). We analyzed two cobbles collected from the tops of roches moutonnées at Crater Lake; one cobble had the equivalent of 3000 yr of exposure, the other < 900 yr.
The evidence for dark matter in binaries and groups of galaxies is very strong, and is seen in all recent observational studies. Measurements of mass in galactic systems is possible on scales ranging from 50 kpc using virial analysis of binary galaxies to 15 Mpc using Virgocentric infall analysis. The Ω estimates derived from these studies are generally consistent with Ω < 0.2, with a fairly weak trend toward larger Ω estimates on larger scales. However, measurements of the galaxy distribution in the IRAS catalog yields a dipole anisotropy consistent in direction with the microwave dipole anisotropy, suggesting that the local galaxy distribution is responsible for the microwave velocity. This will eventually provide the most reliable estimate of Ω, and is likely to result in a value somewhat larger than previous estimates on smaller scales. Study of the velocity field around large clusters in cosmological n-body experiments provides a useful guide for understanding the limitations of the spherically symmetric models of Virgocentric infall. We point out a number of biases that could affect the existing Virgocentric flow studies.
We have completed a redshift survey of approximately 2200 IRAS galaxies, flux limited at 60μ. The survey covers 76% of the sky and has a characteristic depth of ≈ 6000 km s−1, making it ideal for large scale structure studies requiring whole sky coverage. We have calculated the gravitational acceleration on us due to the inhomogeneous distribution of galaxies in the sample by summing the dipole acceleration in successive shells centered on us. The acceleration converges at ≈ 4000 km s−1 and we derive density estimates in the range 0.4 < Ω < 0.9. We discuss the various biases of the sample in detail: the paucity of elliptical galaxies, the problem of extended sources, and hysteresis, and suggest ways to accommodate them and thus decrease the uncertainty in Ω. Finally, we discuss the use of the survey to make predictions for the peculiar velocity flowfield in space.
The statistical nature of the galaxy distribution is in a sense remarkably simple. the two-point correlation function ξ(r), which measures the count of galaxies at separation r in excess of that expected for a random distribution, varies as ξ∝;r−1.8 for ξ>1(r ≲15 Mpc). At larger separations ξ apparently decreases more rapidly. the power law behavior is observed in different galaxy catalogs of varying depth and positions in the sky. What is the explanation of this universal behavior of ξ(r), and what do correlation functions tell us about the initial conditions at the recombination epoch and/or the value of Ω?
Burnout occurs among students when they suddenly lose interest in their studies due to feeling physically and emotionally drained. They experience further emotional depletion due to study demands, distrustfulness and detachment about their work. This study investigated the relationship between the Five-Factor Model (FFM) personality traits and burnout, as operationalised by Maslach's three dimensions of burnout, namely exhaustion, cynicism and reduced personal efficacy. Previous Western research was replicated in order to contribute to the cross-cultural literature on burnout. The Maslach Burnout Inventory – Student Survey University Form and the NEO – Personality Inventory Revised Form S were subjected to stepwise forward regression using FFM factors and facets to predict the scores on each burnout dimension. Five hundred and seventy-seven Filipino college students (age 17 to 24) from private universities and colleges within Metro Manila participated. Results revealed that neuroticism and conscientiousness predict all three burnout constructs. However, certain facets of neuroticism and conscientiousness are more important than others. At the facet level, facets of agreeableness and openness contributed to prediction of burnout as well.
Benchmarks for antimicrobial consumption measured in antimicrobial days are beginning to emerge. The relationship between the traditional measure of days of therapy and antimicrobial days is unclear. We observed a high intermethod correlation (R2=0.99): antimicrobial days were 1.9-fold lower than days of therapy across agents. Individual institutions should correlate these measures.
From analysis of the DIRBE weekly averaged sky maps, we have detected substantial flux in the 60 μm and 100 μm channels in excess of expected zodiacal and Galactic emission (Finkbeiner, D.P., et al. 2000, ApJ, to be published, astro-ph/0004175). Two methods are used to separate zodiacal light from more distant emission. Both methods give consistent results at 60 μm and 100 μm. The observed signal is consistent with an isotropic background of vIv = 28.1 ± 1.8 ± 7 (syst) nWm−2sr−1 at 60 μm and 24.6 ± 2.5 ± 8 (syst) nW m−2 sr−1 at 100 μm.
The IR excess detected at 140 and 240 μm by these methods agrees with previous measurements, which are thought to be the cosmic infrared background (CIB). The detections at 60 and 100 μm are new. While this new excess is not necessarily the CIB, we have ruled out all known sources of emission in the solar system and Galaxy. We therefore tentatively interpret this signal as the CIB and consider the implications of such energy production from the viewpoint of star formation efficiency and black hole accretion efficiency. However, the IR excess exceeds limits on the CIB derived from the inferred opacity of the intergalactic medium to observed TeV photons, thus casting doubt on this interpretation. There is currently no satisfactory explanation for the 60 – 100 μm excess.
We have reprocessed the IRAS and DIRBE full-sky 100 μm maps, using Hi as a zero-point, to produce a map of Galactic extinction. This map is crosscorrelated with APM galaxy counts over the full APM region, including dusty regions of the sky not used to compute the APM correlation function in Maddox et al.(1990a). The angular correlation function, w(θ), of galaxy counts is computed with and without the extinction correction, and is used to suggest that our map accounts for ~ 90% of the dust-induced correlation in the APM region on scales from 2 – 10°. This is the first time that a limit has been placed on the correlation function of the extinction not represented in a given map.
An analysis of all observations of the “twin” QSOs, 0957+561 A, B, to date does not yet allow us to distinguish between their being two nearly identical QSOs or a single QSO split into two images by an intervening gravitational lens. The more identical the two objects are found to be, the more difficult any explanation which postulates the existence of two distinct QSOs becomes. Jodrell Bank and VLA observations reveal additional radio structure to the northeast of the northern QSO image which, if physically associated with a single QSO doubly imaged by a gravitational lens, would itself be imaged weakly to the southwest. More detailed radio mapping should be able to test the existence of such an image.
The VLBI map of Porcas and his collaborators reveals that the radio images corresponding to the optical ones are point sources separated by 6.175 arcsec having an angular extent to less than 20 milliarcseconds, whereas all further radio structure is resolved out.
Optical spectroscopy of the twins reveals two nearly identical sources with indistinguishable emission line redshifts and with absorption line redshifts identical to within 15 km/sec. It is the identity of these optical characteristics which makes all non-gravitational lens hypotheses most difficult.
The most compelling test of the lens hypothesis is the measurement of time variations of the two images at as many wavelengths as possible. If brightness variations of one image are repeated by the other after a time interval determined by the details of the observerlens-QSO geometry (such an interval could be of the order of many months or years) the lens hypothesis would be confirmed. Several observations indicate prior variations of the images, and programs to monitor their relative brightness in the future will be of great importance.
Most models of galactic evolution include a high luminosity epoch of bright star formation at a redshift 2 < Z < 100. Past searches have failed to detect galaxies in their “primeval” state, but recent advances in detector technology will soon enable much improved searches that will very seriously constrain the evolutionary models. Using the CCD detectors on the Space Telescope offers the opportunity for a thousandfold improvement over present search limits. We review here several models of primeval galaxies and comment on their observability in present and future experiments.
Objectives: Licensing of, and coverage decisions on, new therapies should rely on evidence from patient-relevant endpoints such as overall survival (OS). Nevertheless, evidence from surrogate endpoints may also be useful, as it may not only expedite the regulatory approval of new therapies but also inform coverage decisions. It is, therefore, essential that candidate surrogate endpoints be properly validated. However, there is no consensus on statistical methods for such validation and on how the evidence thus derived should be applied by policy makers.
Methods: We review current statistical approaches to surrogate-endpoint validation based on meta-analysis in various advanced-tumor settings. We assessed the suitability of two surrogates (progression-free survival [PFS] and time-to-progression [TTP]) using three current validation frameworks: Elston and Taylor's framework, the German Institute of Quality and Efficiency in Health Care's (IQWiG) framework and the Biomarker-Surrogacy Evaluation Schema (BSES3).
Results: A wide variety of statistical methods have been used to assess surrogacy. The strength of the association between the two surrogates and OS was generally low. The level of evidence (observation-level versus treatment-level) available varied considerably by cancer type, by evaluation tools and was not always consistent even within one specific cancer type.
Conclusions: Not in all solid tumors the treatment-level association between PFS or TTP and OS has been investigated. According to IQWiG's framework, only PFS achieved acceptable evidence of surrogacy in metastatic colorectal and ovarian cancer treated with cytotoxic agents. Our study emphasizes the challenges of surrogate-endpoint validation and the importance of building consensus on the development of evaluation frameworks.
Comparison of galaxy flows with those predicted from the local galaxy distribution ended as an active field after two analyses came to vastly different conclusions 25 years ago, but that was due to faulty data. All the old results are therefore suspect. With new data collected in the last several years, the problem deserves another look. The goal is to explain the 640 km/s dipole anisotropy of the CMBR. For this we analyze the gravity field inferred from the enormous data set derived from the 2MASS collection of galaxies (Huchra et al. 2005), and compare it to the velocity field derived from the well calibrated SFI++ Tully-Fisher catalog (Springob et al. 2007). Using the “Inverse Method” to minimize Malmquist biases, within 10,000 km/s the gravity field is seen to predict the velocity field (Davis et al. 2011) to remarkable consistency. This is a beautiful demonstration of linear perturbation theory and is fully consistent with standard values of the cosmological variables.
Heart failure is a common cause of death in patients with muscular dystrophy. Mechanical support may be an important component of long-term heart failure therapy in these patients. We present a report of a child with muscular dystrophy successfully implanted with a Heartware HVAD.