1,483 research outputs found
Shorted Operators Relative to a Partial Order in a Regular Ring
In this paper, the explicit form of maximal elements, known as shorted
operators, in a subring of a von Neumann regular ring has been obtained. As an
application of the main theorem, the unique shorted operator (of electrical
circuits) which was introduced by Anderson-Trapp has been derived.Comment: There was a small mistake in the published version which has been
corrected her
Session:management of drainage near source – disconnection/minimise surface water entering public drainage
Many combined sewer networks are currently constrained due to lack of capacity. Surface water entering the network may have an impact on the local environment by causing additional spills from Combined Sewer Overflows (CSOs) and flooding events. With the increasing number of developments taking place in Scotland, more and more demands are being placed upon the existing wastewater assets and infrastructure of the drainage utility, Scottish Water. The principal way of preventing these CSO spills/flooding event s is to reduce the number of surface water connections to the combined sewer network and promote more surface water discharges to nearby watercourses.The problem is being addressed by examining all development applications as they are considered by a drainage planning officer in the water authority. The research reported in this paper is investigating the conditions under which it is reasonable and practical for Scottish Water to accept surface water flows into its combined sewer network . This paper presents a summary of the initial findings of the research to date by examining a sample of the sites examined. The objective of the work is to develop a methodology to support a rigorous stance on the acceptance of surface water flows into the combined sewer network. The results have not as yet been obtained
The implausibility of ‘usual care’ in an open system: sedation and weaning practices in Paediatric Intensive Care Units (PICUs) in the United Kingdom (UK)
Background: The power of the randomised controlled trial depends upon its capacity to operate in a closed
system whereby the intervention is the only causal force acting upon the experimental group and absent in the
control group, permitting a valid assessment of intervention efficacy. Conversely, clinical arenas are open systems
where factors relating to context, resources, interpretation and actions of individuals will affect implementation and
effectiveness of interventions. Consequently, the comparator (usual care) can be difficult to define and variable in
multi-centre trials. Hence outcomes cannot be understood without considering usual care and factors that may
affect implementation and impact on the intervention.
Methods: Using a fieldwork approach, we describe PICU context, ‘usual’ practice in sedation and weaning from
mechanical ventilation, and factors affecting implementation prior to designing a trial involving a sedation and
ventilation weaning intervention. We collected data from 23 UK PICUs between June and November 2014 using
observation, individual and multi-disciplinary group interviews with staff.
Results: Pain and sedation practices were broadly similar in terms of drug usage and assessment tools. Sedation
protocols linking assessment to appropriate titration of sedatives and sedation holds were rarely used (9 % and 4 %
of PICUs respectively). Ventilator weaning was primarily a medical-led process with 39 % of PICUs engaging senior
nurses in the process: weaning protocols were rarely used (9 % of PICUs). Weaning methods were variably based
on clinician preference. No formal criteria or use of spontaneous breathing trials were used to test weaning
readiness. Seventeen PICUs (74 %) had prior engagement in multi-centre trials, but limited research nurse
availability. Barriers to previous trial implementation were intervention complexity, lack of belief in the evidence and
inadequate training. Facilitating factors were senior staff buy-in and dedicated research nurse provision.
Conclusions: We examined and identified contextual and organisational factors that may impact on the
implementation of our intervention. We found usual practice relating to sedation, analgesia and ventilator weaning
broadly similar, yet distinctively different from our proposed intervention, providing assurance in our ability to
evaluate intervention effects. The data will enable us to develop an implementation plan; considering these factors
we can more fully understand their impact on study outcomes
Stakeholder involvement in wastewater treatment design
The design option appraisal stage of new water industry capital investment projects involve greater levels of complexity than those generally encountered in other stages of the design process. It is at this stage that the issues related to sustainable development will be introduced, as decisions are multi-stakeholder and therefore decision criteria that reflect the views of a wide range of stakeholders with a range of different viewpoints need to be incorporated. This paper describes a case study which maps information flows, identifies decision criteria and evaluates the extent of stakeholder involvement in the design stage of a major UK wastewater system project. A mapping technique was developed to document and represent the flow of information during the decision making process. An in-depth study of the information flows enabled the researchers to establish the extent to which sustainability criteria were actually used. This was compared with recognised sustainability criteria identified in previous research involving the authors to allow an assessment of the effectiveness of stakeholder representation. Recommendations are given regarding ways of improving stakeholder involvement in water industry asset investment decisions
Domestic source of phosphorus to sewage treatment works.
Phosphorus is an element essential for life. Concerns regarding long-term security of supply and issues related to eutrophication of surface waters once released into the aquatic environment have led governments to consider and apply measures for reducing the use and discharge of phosphorus. Examples of source control include legislation to reduce phosphorus use in domestic detergents. This research shows that other domestic sources of phosphorus also contribute significantly to the domestic load to sewer and that overall, domestic sources dominate loads to sewage treatment works. Estimates provided here show that although the natural diet contributes 40% of the domestic phosphorus load, other potentially preventable sources contribute significantly to the estimated 44,000 tonnes of phosphorus entering UK sewage treatment works each year. In the UK, food additives are estimated to contribute 29% of the domestic load; automatic dishwashing detergents contribute 9% and potentially increasing; domestic laundry 14%, including contributions from phosphonates, but decreasing; phosphorus dosing to reduce lead levels in tap water 6%; food waste disposed of down the drain 1%; and personal care products 1%. Although UK data is presented here, it is anticipated that similar impacts would be expected for other developed economies. Consideration of alternatives to all preventable sources of phosphorus from these sources would therefore offer potentially significant reductions in phosphorus loads to sewage treatment works and hence to the aquatic environment. Combining all source control measures and applying them to their maximum extent could potentially lead to the prevention of over 22,000 tonnes-P/year entering sewage treatment works
Income Distribution Dependence of Poverty Measure: A Theoretical Analysis
With a new deprivation (or poverty) function, in this paper, we theoretically
study the changes in poverty with respect to the `global' mean and variance of
the income distribution using Indian survey data. We show that when the income
obeys a log-normal distribution, a rising mean income generally indicates a
reduction in poverty while an increase in the variance of the income
distribution increases poverty. This altruistic view for a developing economy,
however, is not tenable anymore once the poverty index is found to follow a
pareto distribution. Here although a rising mean income indicates a reduction
in poverty, due to the presence of an inflexion point in the poverty function,
there is a critical value of the variance below which poverty decreases with
increasing variance while beyond this value, poverty undergoes a steep increase
followed by a decrease with respect to higher variance. Following these
results, we make quantitative predictions to correlate a developing with a
developed economy.Comment: 13 pages in single spaced latex, 4 figures, submitted to
'Econometrica
Siege of Gerona [Material cartográfico]
A la part inferior de la là mina: William Blagkood & soons, Edinburgh & LondonMapa gravat, representades les bateries de l'exèrcit frencès en color blau. Xarxa de camins, arbres i conreus. Ombrejat del relleuCopia digital. Madrid : Ministerio de Cultura. Subdirección General de Coordinación Bibliotecaria, 200
Structure of the hexameric HerA ATPase reveals a mechanism of translocation-coupled DNA-end processing in archaea.
The HerA ATPase cooperates with the NurA nuclease and the Mre11-Rad50 complex for the repair of double-strand DNA breaks in thermophilic archaea. Here we extend our structural knowledge of this minimal end-resection apparatus by presenting the first crystal structure of hexameric HerA. The full-length structure visualizes at atomic resolution the N-terminal HerA-ATP synthase domain and a conserved C-terminal extension, which acts as a physical brace between adjacent protomers. The brace also interacts in trans with nucleotide-binding residues of the neighbouring subunit. Our observations support a model in which the coaxial interaction of the HerA ring with the toroidal NurA dimer generates a continuous channel traversing the complex. HerA-driven translocation would propel the DNA towards the narrow annulus of NurA, leading to duplex melting and nucleolytic digestion. This system differs substantially from the bacterial end-resection paradigms. Our findings suggest a novel mode of DNA-end processing by this integrated archaeal helicase-nuclease machine.The SAXS data collection was supported by funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under BioStruct-X (grant agreement N°283570). Research in the N.P.R. laboratory is funded by the Medical Research Council [Career Development Award G0701443]. Research in the L.P. laboratory is funded by a Wellcome Trust Senior Fellowship Award in Basic Biomedical Sciences [grant number 08279/Z/07/Z]. Work in the L.P. and N.P.R. laboratories is also supported by an Isaac Newton Trust Research Grant, and S.M.B. is supported by a BBSRC Doctoral Training Grant.This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/ncomms650
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