Preferred Basis in a Measurement Process

The effect of decoherence is analysed for a free particle, interacting with an environment via a dissipative coupling. The interaction between the particle and the environment occurs by a coupling of the position operator of the particle with the environmental degrees of freedom. By examining the exact solution of the density matrix equation one finds that the density matrix becomes completely diagonal in momentum with time while the position space density matrix remains nonlocal. This establishes the momentum basis as the emergent 'preferred basis' selected by the environment which is contrary to the general expectation that position should emerge as the preferred basis since the coupling with the environment is via the position coordinate.Comment: Standard REVTeX format, 10 pages of output. Accepted for publication in Phys. Rev

A hybrid intelligent agent for notification of users distracted by mobile phones in an urban environment

Mobile devices are now ubiquitous in daily life and the number of activities that can be performed using them is continually growing. This implies increased attention being placed on the device and diverted away from events taking place in the surrounding environment. The impact of using a smartphone on pedestrians in the vicinity of urban traffic has been investigated in a multimodal, fully immersive, virtual reality environment. Based on experimental data collected, an agent to improve the attention of users in such situations has been developed. The proposed agent uses explicit, contextual data from experimental conditions to feed a statistical learning model. The agent’s decision process is aimed at notifying users when they become unaware of critical events in their surroundings

Getting back to work after injury: the UK Burden of Injury multicentre longitudinal study

Background Injuries to working age adults are common and place a considerable burden on health services accounting for more than 10% of GP sick notes and 14% of those claiming benefits because they are unable to work in the UK. General practitioners (GPs) currently assess fitness to work and provide care and referral to other services to facilitate return to work (RTW). Recent UK recommendations suggest replacing GP sickness certification with independent assessments of fitness to work after four weeks sick leave. The impact of a wide range of injuries on RTW and subsequent need for independent fitness to work assessments has not been well studied in the UK. The aim of this study was to quantify RTW and factors predicting RTW following a wide range of injuries. Methods We used a multicentre longitudinal study, set in four acute NHS Trusts in the UK which recruited emergency department (ED) attenders and hospital admissions for injury and included those aged 16–65years that were employed or self-employed before the injury. Participants were followed up by postal questionnaire at 1, 4 and 12 months post injury to measure health status (EQ-5D), recovery, use of health and social services, time off work in the preceding month and work problems amongst those who had RTW. Multivariable Poisson regression with a robust variance estimator was used to estimate relative risks for factors associated with RTW. Results One month after injury 35% of ED attenders had fully RTW. The self employed were more likely (RR 1.70, 95% CI 1.17 to 2.47 compared with employed) and the moderate/severely injured less likely to RTW (RR 0.48, 95% CI 0.32 to 0.72 compared with minor injuries). At four months, 83% of ED attenders had RTW and self employment and injury severity remained significant predictors of RTW (self employment RR 1.15, 95% CI 1.03 to 1.30; moderate/severe injury RR 0.79, 95% CI 0.68 to 0.92). At four months 57% of hospital admissions had RTW. Men were more likely than women to RTW (RR 1.94, 95% CI 1.34 to 2.82), whilst those injured at work (RR 0.49, 95% CI 0.27 to 0.87 compared with at home) and those living in deprived areas (most deprived tertile RR 0.59, 95% CI 0.40 to 0.85 and middle tertile RR 0.61, 95% CI 0.40 to 0.93) were less likely to RTW. Health status was significantly poorer at one and four months after injury than before the injury and was significantly poorer amongst those that had not RTW compared to those that had. Problems with pain control, undertaking usual activities, mobility and anxiety and depression were common and persisted in a considerable proportion of participants up to four months post injury. Conclusions Injuries have a large impact on time off work, including amongst those whose injuries did not warrant hospital admission. The majority of injured people would require an in-depth fitness for work assessment if recent UK recommendations are implemented. Many people will have on-going pain, mobility problems, anxiety and depression at the point of assessment and it is important that patients are encouraged to use primary care services to address these problems. A range of factors may be useful for identifying those at risk of a slower recovery and a delayed RTW so that appropriate interventions can be provided to this group

Myosin-I nomenclature.

We suggest that the vertebrate myosin-I field adopt a common nomenclature system based on the names adopted by the Human Genome Organization (HUGO). At present, the myosin-I nomenclature is very confusing; not only are several systems in use, but several different genes have been given the same name. Despite their faults, we believe that the names adopted by the HUGO nomenclature group for genome annotation are the best compromise, and we recommend universal adoption

Beyond element-wise interactions: identifying complex interactions in biological processes

Background: Biological processes typically involve the interactions of a number of elements (genes, cells) acting on each others. Such processes are often modelled as networks whose nodes are the elements in question and edges pairwise relations between them (transcription, inhibition). But more often than not, elements actually work cooperatively or competitively to achieve a task. Or an element can act on the interaction between two others, as in the case of an enzyme controlling a reaction rate. We call “complex” these types of interaction and propose ways to identify them from time-series observations. Methodology: We use Granger Causality, a measure of the interaction between two signals, to characterize the influence of an enzyme on a reaction rate. We extend its traditional formulation to the case of multi-dimensional signals in order to capture group interactions, and not only element interactions. Our method is extensively tested on simulated data and applied to three biological datasets: microarray data of the Saccharomyces cerevisiae yeast, local field potential recordings of two brain areas and a metabolic reaction. Conclusions: Our results demonstrate that complex Granger causality can reveal new types of relation between signals and is particularly suited to biological data. Our approach raises some fundamental issues of the systems biology approach since finding all complex causalities (interactions) is an NP hard problem

Population based estimates of non-fatal injuries in the capital of Iran

<p>Abstract</p> <p>Background</p> <p>Fatal injuries are at the top of the injury pyramid; however, non-fatal injuries are quite common and impose huge medical expenses on the population. Relying on hospital data will underestimate the incidence of non-fatal injuries. The aim of this study was to estimate the annual incidence and out of pocket medical expenses of all injuries in urban population of Tehran (the capital city of Iran).</p> <p>Methods</p> <p>Using the cluster random sampling approach, a household survey of residents of greater Tehran was performed on April 2008. At randomly selected residential locations, interviewers asked one adult person to report all injuries which have occurred during the past year for all household members, as well as the type of injury, place of occurrence, the activity, cause of accidents resulting in injuries, the amount of out of pocket medical expenses for injury, and whether they referred to hospital.</p> <p>Results</p> <p>This study included 2,450 households residing in Tehran during 2007-8. The annual incidence of all injuries was 188.7 (180.7-196.9), significant injuries needing any medical care was 68.8 (63.7-74.2), fractures was 19.3 (16.6 - 22.4), and injuries resulted in hospitalization was 16.7 (14.2 - 19.6) per 1000 population. The annual incidence of fatal injuries was 33 (7-96) per 100,000 Population. In children aged 15 or less, the annual incidence of all injuries was 137.2 (120.0 - 155.9), significant injuries needing any medical care was 64.2 (52.2 - 78.0), fractures was 21.8 (15.0 - 30.7), and injuries resulted in hospitalization was 6.8 (3.3 - 12.5) per 1000 population. The mean out of pocket medical expense for injuries was 19.9 USD.</p> <p>Conclusion</p> <p>This population based study showed that the real incidence of non-fatal injuries in the capital of Iran is more than the formal hospital-based estimates. These injuries impose non trivial medical and indirect cost on the community. The out of pocket medical expense of non-fatal injuries to Tehran population is estimated as 27 million USD per year. Effective strategies should be considered to minimize these injuries and decrease the great financial burden to public and the health system.</p

Which treatment for low back pain? A factorial randomised controlled trial comparing intravenous analgesics with oral analgesics in the emergency department and a centrally acting muscle relaxant with placebo over three days [ISRCTN09719705]

BACKGROUND: About two thirds of adults suffer from backpain at some time during their life. In the emergency room many patients with acute back pain are treated with intravenous non-steroidal analgesics. Whether this treatment is superior to oral administration of non-steroidal analgesics is unknown. Intravenous administration, however, requires considerable amounts of resources and accounts for high workload in busy clinics. In the further course centrally acting muscle relaxants are prescribed but the effectiveness remains unclear. The objective of this study is on the one hand to compare the effectiveness of intravenous with oral non-steroidal analgesics for acute treatment and on the other hand to compare the effectiveness of a centrally active muscle relaxant with placebo given for three days after presentation to the ED (emergency department). METHODS/DESIGN: This study is intended as a randomised controlled factorial trial mainly for two reasons: (1) the sequence of treatments resembles the actual proceedings in every-day clinical practice, which is important for the generalisability of the results and (2) this design allows to take interactions between the two sequential treatment strategies into account. There is a patient preference arm included because patients preference is an important issue providing valuable information: (1) it allows to assess the interaction between desired treatment and outcome, (2) results can be extrapolated to a wider group while (3) conserving the advantages of a fully randomised controlled trial. CONCLUSION: We hope to shed more light on the effectiveness of treatment modalities available for acute low back pain

Psychological morbidity and health related quality of life after injury: multicentre cohort study

Purpose: To demonstrate the impact of psychological morbidity 1 month post-injury on subsequent post-injury quality of life (HRQoL) in a general injury population in the UK to inform development of trauma care and rehabilitation services. Methods: Multicentre cohort study of 16–70-year-olds admitted to 4 UK hospitals following injury. Psychological morbidity and HRQoL (EQ-5D-3L) were measured at recruitment and 1, 2, 4 and 12 months post-injury. A reduction in EQ-5D compared to retrospectively assessed pre-injury levels of at least 0.074 was taken as the minimal important difference (MID). Multilevel logistic regression explored relationships between psychological morbidity 1 month post-injury and MID in HRQoL over the 12 months after injury. Results: A total of 668 adults participated. Follow-up rates were 77% (1 month) and 63% (12 months). Substantial reductions in HRQoL were seen; 93% eported a MID at 1 month and 58% at 12 months. Problems with pain, mobility and usual activities were commonly reported at each time point. Depression and anxiety scores month post-injury were independently associated with subsequent MID in HRQoL. The relationship between depression and HRQoL was partly explained by anxiety and to a lesser extent by pain and social functioning. The relationship between anxiety and HRQoL was not explained by factors measured in our study. Conclusions: Hospitalised injuries result in substantial reductions in HRQoL up to 12 months later. Depression and anxiety early in the recovery period are independently associated with lower HRQoL. Identifying and managing these problems, ensuring adequate pain control and facilitating social functioning are key elements in improving HRQoL post-injury

Unintentional injuries in children with disabilities:a systematic review and meta-analysis

Children with disabilities are thought to have an increased risk of unintentional injuries, but quantitative syntheses of findings from previous studies have not been done. We conducted a systematic review and meta-analysis to assess whether pre-existing disability can increase the risk of unintentional injuries among children when they are compared to children without disability. We searched 13 electronic databases to identify original research published between 1 January 1990 and 28 February 2013. We included those studies that reported on unintentional injuries among children with pre-existing disabilities compared with children without disabilities. We conducted quality assessments and then calculated pooled odds ratios of injury using random-effects models. Fifteen eligible studies were included from 24,898 references initially identified, and there was a total sample of 83,286 children with disabilities drawn from the eligible studies. When compared with children without disabilities, the pooled OR of injury was 1.86 (95 % CI 1.65-2.10) in children with disabilities. The pooled ORs of injury were 1.28, 1.75, and 1.86 in the 0-4 years, 5-9 years, and ≥10 years of age subgroups, respectively. Compared with children without disabilities, the pooled OR was 1.75 (95 % CI 1.26-2.43) among those with International Classification of Functioning (ICF) limitations. When disability was defined as physical disabilities, the pooled OR was 2.39 (95 % CI 1.43-4.00), and among those with cognitive disabilities, the pooled OR was 1.77 (95 % CI 1.49-2.11). There was significant heterogeneity in the included studies. Compared with peers without disabilities, children with disabilities are at a significantly higher risk of injury. Teens with disabilities may be an important subgroup for future injury prevention efforts. More data are needed from low- and middle-income countries