3,550 research outputs found
Peripheral Meson Model of Deep Inelastic Rapidity Gap Events
We show that a peripheral meson model can explain the large deep inelastic
electron-proton scattering rapidity gap events observed at HERA.Comment: 12 pages, 2 figure
Do management practices matter in further education?
Further education and sixth form colleges are key institutions for facilitating skill acquisition among 16–19 year olds in the UK. They enrol half a school cohort after completion of their lower secondary education, and this includes a disproportionate number from low-income backgrounds. Yet little is known about what could improve performance in these institutions. We conduct the world's first management practices survey in such institutions, and match this to administrative longitudinal data on over 40,000 students. Value-added regressions with rich controls suggest that structured management matters for educational outcomes, especially for students from low-income backgrounds. For this group, in a hypothetical scenario where an individual is moved from a college at the 10th percentile of management practices to the 90th, this would be associated with 8% higher probability of achieving a good high school qualification, nearly half of the educational gap between those from poor and non-poor backgrounds. Hence improving management practices may be an important channel for reducing inequalities
Cryptic disease-induced mortality may cause host extinction in an apparently stable host- parasite system
The decline of wildlife populations due to emerging infectious disease often shows a common pattern: the parasite invades a naive host population, producing epidemic disease and a population decline, sometimes with extirpation. Some susceptible host populations can survive the epidemic phase and persist with endemic parasitic infection. Understanding host–parasite dynamics leading to persistence of the system is imperative to adequately inform conservation practice. Here we combine field data, statistical and mathematical modelling to explore the dynamics of the apparently stable Rhinoderma darwinii–Batrachochytrium dendrobatidis (Bd) system. Our results indicate that Bd-induced population extirpation may occur even in the absence of epidemics and where parasite prevalence is relatively low. These empirical findings are consistent with previous theoretical predictions showing that highly pathogenic parasites are able to regulate host populations even at extremely low prevalence, highlighting that disease threats should be investigated as a cause of population declines even in the absence of an overt increase in mortality
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A Pilot Study into the Use of Qualitative Methods to Improve the Awareness of Barriers to Sustainable Medical Waste Segregation within the United Kingdom’s National Health Service
Data Availability Statement:
The data presented in this study are available on request from the corresponding author.Within the United Kingdom, most medical waste is incorrectly classified as hazardous and disposed of via incineration or alternative treatment. Currently, no research has been conducted on why such a large quantity of medical waste is erroneously segregated. This pilot study explores the barriers to correct segregation with the aim to decrease the volume of incinerated waste by investigating why medical waste is wrongly identified as hazardous. No previous data are available to compare results, and so this study demonstrates the significance of using qualitative methods (questionnaires and focus groups) to bring awareness to issues faced within medical facilities when segregating waste. The low availability of different bins as well as lack of space and the healthcare workers’ busy schedules were identified as main reasons for poor segregation. Bins were sparsely placed, and staff lacked time to find the appropriate one leading to incorrect segregation of non-hazardous waste. Lack of information around whether a material was recyclable or not led to less recycled waste. When ways to engage with this issue were discussed, most medical staff favoured quick forms of information provision, such as posters, whereas a participant proclaimed longer hands-on style sessions as more effective. The findings of this study provide evidence that governmental strategies focused on sustainable medical waste management should direct their attention to the placement and availability of bins, whilst including ‘on-the-ground’ personnel in their decision making. This pilot study showed the value in using qualitative methods when current data are lacking and can be repeated by other healthcare facilities to collectively grow a greater awareness of the sustainability issues faced by the UK healthcare waste management system.This research was undertaken whilst receiving a studentship by a UK medical device manufacturer
Circular waste management of electric vehicle batteries: legal and technical perspectives from the EU and the UK post Brexit
Copyright © 2021 The Authors. In light of the climate change, interdisciplinary solutions are needed to deal with end-of-life lithium-ion batteries (LIBs) that are used in Electric vehicles (EVs) in order to avoid a waste problem in the future. Building on both legal and technical perspectives, this paper criticises the current EU and UK frameworks and policies on batteries waste management which fail to address technological innovation, especially, in terms of the creation of a market for ‘second life’ of EV batteries which are subject to the electrochemical performance and durability and safety parameters, as well as LIB recycling in support of a circular economy. Most importantly, it also addresses recent developments in the EU in terms of a proposal for the EU new Batteries Regulation and the impact of Brexit in the UK for its future policy shape
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Environmental impacts of different waste to food approaches
All waste treatment options have environmental impacts. As waste to food is one of the many possible ways to valorise (or treat) food waste, environmental impacts of different waste to food processes need to be compared alongside other waste treatment methods. In addition, the environmental impact of the prevention of waste needs to also be compared to waste to food impacts. This chapter introduces the method of life cycle assessment (LCA) to evaluate the environmental impacts of various production and treatment options. We highlight multiple methods to conduct environmental impact assessment, including a bottom up LCA, or a hybrid IO-LCA approach. We cover the drawbacks and limits of these different LCA methods. We highlight best practice waste to food environmental assessment case studies, including the REFRESH FORKLIFT toolkit. We intend for this chapter to be a broad introduction to these topics, empowering a decision maker or researcher to understand the processes, and limits of waste to food environmental impact assessments
Disk Evolution in W5: Intermediate Mass Stars at 2-5 Myr
We present the results of a survey of young intermediate mass stars (age
~5 Myr, 1.5 15 ) in the W5 massive star
forming region. We use combined optical, near-infrared and {\it Spitzer} Space
Telescope photometry and optical spectroscopy to define a sample of stars of
spectral type A and B and examine their infrared excess properties. We find
objects with infrared excesses characteristic of optically thick disks, i.e.
Herbig AeBe stars. These stars are rare: 1.5% of the entire spectroscopic
sample of A and B stars, and absent among stars more massive than 2.4
. 7.5% of the A and B stars possess infrared excesses in a variety of
morphologies that suggest their disks are in some transitional phase between an
initial, optically thick accretion state and later evolutionary states. We
identify four morphological classes based on the wavelength dependence of the
observed excess emission above theoretical photospheric levels: (a) the
optically thick disks; (b) disks with an optically thin excess over the
wavelength range 2 to 24 \micron, similar to that shown by Classical Be
stars; (c) disks that are optically thin in their inner regions based on their
infrared excess at 2-8 \micron and optically thick in their outer regions
based on the magnitude of the observed excess emission at 24 \micron; (d)
disks that exhibit empty inner regions (no excess emission at
8 \micron) and some measurable excess emission at 24 \micron. A sub-class
of disks exhibit no significant excess emission at 5.8
\micron, have excess emission only in the {\it Spitzer} 8 \micron band and
no detection at 24 \micron. We discuss these spectral energy distribution
(SED) types, suggest physical models for disks exhibiting these emission
patterns and additional observations to test these theories.Comment: 35 pages, 10 figures, accepted to Astrophysical Journa
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