Disability in young people and adults after head injury: 12-14 year follow up of a prospective cohort

Background: There is a need to establish how long term outcome evolves after head injury (HI) and factors related to this, to inform opportunities for intervention. Objective: To determine late outcome in adults 12-14 years after hospital admission for HI and to examine relationships between injury, early and late factors and disability. Methods: A prospective cohort with HI, whose outcome was reported previously at 1 and 5-7 years after injury were followed up after 12-14 years. Participants were assessed using structured and validated measures of disability (Glasgow Outcome Scale-Extended), psychological well-being, alcohol use and health status. Results: Of 219 survivors followed-up at 5-7 years, 34 (15.5%) had died by 12-14 years. Disability remained common in survivors at 12-14 years (51%), as found at one and 5-7 years (53%). For those disabled at 1 year, outcome was dismal, with 80% dead or disabled at 12-14 years. Older age at injury, a premorbid history of brain illness or physical disability and post-injury low self-esteem and stress were associated with disability at 12-14 years. Disability changed between 5-7 and 12-14 years in 55% of survivors, improving in 23%. Late changes in disability between 5-7 and 12-14 years were associated with self-perceptions of locus of control as being 'powerful others' at 5-7 years. Conclusions: Disability is common 12-14 years after hospital admission with a head injury. For some there is a dynamic process of change in disability over time that is associated with self-perceptions of control that could be a target for intervention based research

Models for the Effects of G-seat Cuing on Roll-axis Tracking Performance

Including whole-body motion in a flight simulator improves performance for a variety of tasks requiring a pilot to compensate for the effects of unexpected disturbances. A possible mechanism for this improvement is that whole-body motion provides high derivative vehicle state information whic allows the pilot to generate more lead in responding to the external disturbances. During development of motion simulating algorithms for an advanced g-cuing system it was discovered that an algorithm based on aircraft roll acceleration producted little or no performance improvement. On the other hand, algorithms based on roll position or roll velocity produced performance equivalent to whole-body motion. The analysis and modeling conducted at both the sensory system and manual control performance levels to explain the above results are described

Enhanced recovery after surgery

Enhanced Recovery or Fast Track Recovery after Surgery protocols (ERAS) have significantly changed perioperative care following colorectal surgery and are promoted as reducing the stress response to surgery. The present systematic review aimed to examine the impact on the magnitude of the systemic inflammatory response (SIR) for each ERAS component following colorectal surgery using objective markers such as C-reactive protein (CRP) and interleukin-6 (IL-6). A literature search was performed of the US National Library of Medicine (MEDLINE), EMBASE, PubMed, and the Cochrane Database of Systematic Reviews using appropriate keywords and subject headings to February 2015. Included studies had to assess the impact of the selected ERAS component on the SIR using either CRP or IL-6. Nineteen studies, including 1898 patients, were included. Fourteen studies (1246 patients) examined the impact of laparoscopic surgery on the postoperative markers of SIR. Ten of these studies (1040 patients) reported that laparoscopic surgery reduced postoperative CRP. One study (53 patients) reported reduced postoperative CRP using opioid-minimising analgesia. One study (142 patients) reported no change in postoperative CRP following preoperative carbohydrate loading. Two studies (108 patients) reported conflicting results with respect to the impact of goal-directed fluid therapy on postoperative IL-6. No studies examined the effect of other ERAS components, including mechanical bowel preparation, antibiotic prophylaxis, thromboprophylaxis, and avoidance of nasogastric tubes and peritoneal drains on markers of the postoperative SIR following colorectal surgery. The present systematic review shows that, with the exception of laparoscopic surgery, objective evidence of the effect of individual components of ERAS protocols in reducing the stress response following colorectal surgery is limited

Relationship between emergency presentation, systemic inflammatory response, and cancer-specific survival in patients undergoing potentially curative surgery for colon cancer

Background Emergency presentation is recognized to be associated with poorer cancer-specific survival following curative resection for colorectal cancer. The present study examined the hypothesis that an enhanced systemic inflammatory response, prior to surgery, might explain the impact of emergency presentation on survival. Methods In all, 188 patients undergoing potentially curative resection for colorectal cancer were studied. Of these, 55 (29%) presented as emergencies. The systemic inflammatory response was assessed using the Glasgow Prognostic Score (mGPS), which is the combination of an elevated C-reactive protein (>10 mg/L) and hypoalbuminemia (<35 g/L). Results In the emergency group, tumor stage was greater (P < 0.01), more patients received adjuvant therapy (P < 0.01) more patients had an elevated mGPS (P < 0.01), and more patients died of their disease (P < 0.05). The minimum follow-up was 12 months; the median follow-up of the survivors was 48 months. Emergency presentation was associated with poorer 3-year cancer-specific survival in those patients aged 65 to 74 years (P < 0.01), in both males and females (P < 0.05), in the deprived (P < 0.01), in patients with tumor-node-metastasis (TNM) stage II disease (P < 0.01), in those who received no adjuvant therapy (P < 0.01), and in the mGPS 0 and 1 groups (P < 0.05) groups. On multivariate survival analysis of patients undergoing potentially curative surgery for TNM stage II colon cancer, emergency presentation (P < 0.05) and mGPS (P < 0.05) were independently associated with cancer-specific survival. Conclusions These results suggest that emergency presentation and the presence of systemic inflammatory response prior to surgery are linked and account for poorer cancer-specific survival in patients undergoing potentially curative surgery for colon cancer. Both emergency presentation and an elevated mGPS should be taken into account when assessing the likely outcome of these patients

Interpolation Properties and SAT-based Model Checking

Craig interpolation is a widespread method in verification, with important applications such as Predicate Abstraction, CounterExample Guided Abstraction Refinement and Lazy Abstraction With Interpolants. Most state-of-the-art model checking techniques based on interpolation require collections of interpolants to satisfy particular properties, to which we refer as "collectives"; they do not hold in general for all interpolation systems and have to be established for each particular system and verification environment. Nevertheless, no systematic approach exists that correlates the individual interpolation systems and compares the necessary collectives. This paper proposes a uniform framework, which encompasses (and generalizes) the most common collectives exploited in verification. We use it for a systematic study of the collectives and of the constraints they pose on propositional interpolation systems used in SAT-based model checking

Experimental demonstration of a measurement-based realisation of a quantum channel

We introduce and experimentally demonstrate a method for realising a quantum channel using the measurement-based model. Using a photonic setup and modifying the bases of single-qubit measurements on a four-qubit entangled cluster state, representative channels are realised for the case of a single qubit in the form of amplitude and phase damping channels. The experimental results match the theoretical model well, demonstrating the successful performance of the channels. We also show how other types of quantum channels can be realised using our approach. This work highlights the potential of the measurement-based model for realising quantum channels which may serve as building blocks for simulations of realistic open quantum systems.Comment: 8 pages, 4 figure

Nonlinear predictability of stock market returns: evidence from nonparametric and threshold models

Recent empirical evidence suggests that stock market returns are predictable from a variety of financial and macroeconomic variables. However, with two exceptions this predictability is based upon a linear functional form. This paper extends this research by considering whether a nonlinear relationship exists between stock market returns and these conditioning variables, and whether this nonlinearity can be exploited for forecast improvements. General nonlinearities are examined using a nonparametric regression technique, which suggest possible threshold behaviour. This leads to estimation of a smooth-transition threshold type model, with the results indicating an improved insample performance and marginally superior out-of-sample forecast results. D 2001 Elsevier Scienc

Achieving very low levels of detection : an improved surface-enhanced raman scattering experiment for the physical chemistry teaching laboratory

This experiment was designed and successfully introduced to complement the nanochemistry taught to undergraduate students in a useful and interesting way. Colloidal Ag nanoparticles were synthesized by a simple, room-temperature method, and the resulting suspension was then used to study the surface-enhanced Raman scattering (SERS) of methylene blue. The colloid was also characterized by UV–visible spectroscopy, and these results were used to help explain some of the observed SERS features. The students looked at the effects of concentration and acquisition time on the measured SERS spectra, and the final part of the experiment was based around using their newly acquired knowledge to investigate the lowest concentration of methylene blue that could be detected. Concentrations of 5 × 10-10 M were routinely achieved. The combination of UV–visible spectroscopy, SERS, and nanochemistry made for an interesting and thought-provoking laboratory experience

Splitting Proofs for Interpolation

We study interpolant extraction from local first-order refutations. We present a new theoretical perspective on interpolation based on clearly separating the condition on logical strength of the formula from the requirement on the com- mon signature. This allows us to highlight the space of all interpolants that can be extracted from a refutation as a space of simple choices on how to split the refuta- tion into two parts. We use this new insight to develop an algorithm for extracting interpolants which are linear in the size of the input refutation and can be further optimized using metrics such as number of non-logical symbols or quantifiers. We implemented the new algorithm in first-order theorem prover VAMPIRE and evaluated it on a large number of examples coming from the first-order proving community. Our experiments give practical evidence that our work improves the state-of-the-art in first-order interpolation.Comment: 26th Conference on Automated Deduction, 201