Integrable Impurities as Boundary Conditions

A few exactly solvable interacting quantum many-body problems with impurities were previously reported to exhibit unusual features such as non-localization and absence of backscattering. In this work we consider the use of these integrable impurities as boundary conditions in the framework of linear transport problems. We first show that such impurities enhance the density of states at the Fermi surface, thus increasing the effective system size. The study of the real time-dynamics of a wave packet sent through a series of them inserted in both non-interacting and interacting leads then indicates that these impurities are transparent and do not add artefacts to the measurement of transport properties. We finally apply these new boundary conditions to study the conductance of an interacting scatterer using the embedding method.Comment: 6 figure

LabelFusion: A Pipeline for Generating Ground Truth Labels for Real RGBD Data of Cluttered Scenes

Deep neural network (DNN) architectures have been shown to outperform traditional pipelines for object segmentation and pose estimation using RGBD data, but the performance of these DNN pipelines is directly tied to how representative the training data is of the true data. Hence a key requirement for employing these methods in practice is to have a large set of labeled data for your specific robotic manipulation task, a requirement that is not generally satisfied by existing datasets. In this paper we develop a pipeline to rapidly generate high quality RGBD data with pixelwise labels and object poses. We use an RGBD camera to collect video of a scene from multiple viewpoints and leverage existing reconstruction techniques to produce a 3D dense reconstruction. We label the 3D reconstruction using a human assisted ICP-fitting of object meshes. By reprojecting the results of labeling the 3D scene we can produce labels for each RGBD image of the scene. This pipeline enabled us to collect over 1,000,000 labeled object instances in just a few days. We use this dataset to answer questions related to how much training data is required, and of what quality the data must be, to achieve high performance from a DNN architecture

Randomised controlled trials of complex interventions and large-scale transformation of services

Complex interventions and large-scale transformations of services are necessary to meet the health-care challenges of the 21st century. However, the evaluation of these types of interventions is challenging and requires methodological development. Innovations such as cluster randomised controlled trials, stepped-wedge designs, and non-randomised evaluations provide options to meet the needs of decision-makers. Adoption of theory and logic models can help clarify causal assumptions, and process evaluation can assist in understanding delivery in context. Issues of implementation must also be considered throughout intervention design and evaluation to ensure that results can be scaled for population benefit. Relevance requires evaluations conducted under real-world conditions, which in turn requires a pragmatic attitude to design. The increasing complexity of interventions and evaluations threatens the ability of researchers to meet the needs of decision-makers for rapid results. Improvements in efficiency are thus crucial, with electronic health records offering significant potential

When is an ounce of prevention worth a pound of cure: The case of cardiovascular disease?

Objective: To provide decision makers with a tool to inform resource allocation decisions at the local level, using cardiovascular disease prevention as an example. Method: Evidence from the international literature was extrapolated to estimate the health and financial impacts in Central Sydney Area Health Service (CSAHS) of three different prevention programs; smoking cessation; blood pressure reduction and cholesterol lowering. The cost-effectiveness analysis framework was reconfigured to 1) estimate the risk of CVD in the community using local risk factor data, 2) estimate the number of CVD events prevented through investment in preventive programs and 3) estimate the local financial flow-on effects of prevention on acute care services. The model developed here estimates an upper bound of what local decision makers could spend on preventive programs whilst remaining consistent with their willingness to pay for one additional life-year gained. Results: The model predicted that over a five-year period the cumulative impact of the three programs has the potential to save 1245 life-years in people aged 40-79 years living in CSAHS. If decision-makers are willing to invest in cost-saving preventive programs only, the model estimates that they can spend up $12 per person in the target group per year. However, if they are willing to spend$70,000 per life-year gained, this amount rises to $201. Conclusions: Modelling the impact of preventive activities on the acute care health system enables us to estimate the amount that can be spent on preventive programs. The model is flexible in terms of its ability to examine these impacts in a variety of settings and therefore has the potential to be a useful resource planning tool.Resource allocation, cardiovascular disease, health promotion, Australia

« Bouger c’est vivre, vivre c’est bouger » :: le plaisir d’apprendre éprouvé par les élèves grâce à l’enseignement en mouvement

« Les élèves ressentent davantage de plaisir dans leurs apprentissages lorsqu’on leur propose une leçon en ajoutant du mouvement » « Les enfants préfèrent bouger plutôt que de rester assis sur leur chaise. » « Malgré le fait qu’ils ne soient pas habitués à ce type de leçon, ils se mettent rapidement au travail. » Voici les trois hypothèses que nous avons confirmées ou contredites dans les prochaines pages. Ce travail de Bachelor qui s’intéresse à l’enseignement en mouvement tente de répondre à la question de recherche suivante : Si les élèves d’une classe du cycle 2 du canton de Neuchâtel éprouvent le plaisir d’apprendre grâce à l’enseignement en mouvement mais que celui-ci est souvent exclu des classes par manque de temps, alors comment pouvons-nous souligner les aspects bénéfiques pour changer cette vision ? Pour répondre à cette question, nous avons filmé deux leçons de mathématiques, l’une sans mouvement, l’autre avec mouvement. Grâce à l’observation de la gestuelle des élèves ainsi qu’aux questionnaires auxquels ils ont répondu, nous avons pu prouver ou contredire nos hypothèses. Le but final de ce travail est de faire changer une ancienne idée qui est enracinée dans notre société qui prétend qu’une activité intellectuelle peut exister sans l’utilisation du corps

Optimal management of urinary tract infections in older people

Urinary tract infections (UTI) occur frequently in older people. Unfortunately, UTI is commonly overdiagnosed and overtreated on the basis of nonspecific clinical signs and symptoms. The diagnosis of a UTI in the older patient requires the presence of new urinary symptoms, with or without systemic symptoms. Urinalysis is commonly used to diagnose infection in this population, however, the evidence for its use is limited. There is overwhelming evidence that asymptomatic bacteriuria should not be treated. Catheter associated urinary tract infection accounts for a significant amount of hospital-associated infection. Indwelling urinary catheters should be avoided where possible and alternatives sought. The use of narrow spectrum antimicrobial agents for urinary tract infection is advocated. Local guidelines are now widely used to reflect local resistance patterns and available agents. Guidelines need to be updated to reflect changes in antimicrobial prescribing and a move from broad to narrow spectrum antimicrobials

Increasing the Affordability of Rental Housing in Canada: An Assessment of Alternative Supply-Side Measures

Homelessness is a serious social problem that is unlikely to be solved by grand proclamations or a single policy initiative. It is, more likely, to be solved by the introduction of innumerable changes both in how we understand the problem and how we approach its solution. In this paper we examine the costs and benefits of tax measures that would promote greater involvement of the private sector in the provision of affordable housing. We also examine the costs and benefits of a variety of regulatory initiatives. In an earlier era, centrally directed federal-provincial grant programs for housing run by governments and non-profit organizations were the means of providing affordable housing. Most of the proposals in this paper, in contrast, aim to harness the energy and the efficiency-promoting competition of the private sector. The focus is on decentralized decision-making. Some measures would depend heavily on individual entrepreneurs and non-profit organizations. Others would depend on municipal governments, whose program capacities have grown greatly in recent decades and whose closeness to their constituencies makes them well-placed both to develop and to deliver supportive measures. Our assessment of possibilities suggests that a low-income housing tax credit best balances effectiveness with the need to minimize costs on strained government budgets. Tax measures aimed at investors in multi-unit rental buildings are also likely to meet these criteria

Hand movement observation by individuals born without hands: phantom limb experience constrains visual limb perception

Increasing evidence suggests that the visual analysis of other people's actions depends upon the observer's own body representation or schema. This raises the question of how differences in observers' body structure and schema impact their perception of human movement. We investigated the visual experiences of two persons born without arms, one with and the other without phantom sensations. These participants, plus six normally-limbed control observers, viewed depictions of upper limb movement under conditions of apparent motion. Consistent with previous results (Shiffrar M, Freyd JJ (1990) Psychol Sci 1:257), normally-limbed observers perceived rate-dependent paths of apparent human movement. Specifically, biologically impossible motion trajectories were reported at rapid display rates while biologically possible trajectories were reported at slow display rates. The aplasic individual with phantom experiences showed the same perceptual pattern as control participants, while the aplasic individual without phantom sensations did not. These preliminary results suggest that phantom experiences may constrain the visual analysis of the human body. These results further suggest that it may be time to move beyond the question of whether aplasic phantoms exist and instead focus on the question of why some people with limb aplasia experience phantom sensations while others do not. In this light, the current results suggest that somesthetic representations are not sufficient to define body schema. Instead, neural systems matching action observation, action execution and motor imagery likely contribute to the definition of body schema in profound ways. Additional research with aplasic individuals, having and lacking phantom sensations, is needed to resolve this issu

The why and wherefore of queenslandplaces.com.au

In an urbanised society most of us live in cities, suburbs, towns and villages. All have a rich and sometimes unexpected history. Over the last seven years a group has been working on a public website to explore Queensland's places. Peter Spearritt, Marion Stell and John Young explain

Barcelona Plays: A Collection of New Works by Catalan Playwrights

Barcelona’s theater has experienced a remarkable renaissance in the years since the end of the Franco dictatorship. Soon the Catalan language, suppressed for more than three decades, became a vehicle of expression for new playwrights who challenged performance groups. This collection represents outstanding Catalan playwrights from three generations.https://scholarship.richmond.edu/bookshelf/1163/thumbnail.jp