Vision Modulates Corticospinal Suppression in a Functionally Specific Manner during Movement of the Opposite Limb

The effect of vision on the excitability of corticospinal projections to the flexor carpi radialis (FCR) and extensor carpi radialis (ECR) muscles of right human forearm was investigated before and during discrete movement of the opposite limb. An external force opposed the initial phase of the movement (wrist flexion) and assisted the reverse phase, so that recruitment of the wrist extensors was minimized. Three conditions were used as follows: viewing the inactive right limb (Vision), viewing the mirror image of the moving left limb (Mirror), and with vision of the right limb occluded (No Vision). Transcranial magnetic stimulation was delivered to the left motor cortex: before, at the onset of, or during the left limb movement to obtain motor evoked potentials (MEPs) in the muscles of the right forearm. At and following movement onset, MEPs obtained in the right FCR were smaller in the Vision condition than in the Mirror and No Vision conditions. A distinct pattern of variation was obtained for the ECR. In all conditions, MEPs in this muscle were elevated upon or following movement of the opposite limb. An additional analysis of ipsilateral silent periods indicated that interhemispheric inhibition plays a role in mediating these effects. Activity-dependent changes in corticospinal output to a resting limb during discrete actions of the opposite limb are thus directly contingent upon where one looks. Furthermore, the extent to which vision exerts an influence upon projections to specific muscles varies in accordance with the functional contribution of their homologs to the intended action.

Differences in the diagnostic yield of upper gastrointestinal endoscopy in dyspeptic patients receiving proton-pump inhibitors and H2-receptor antagonists

Patients attending for diagnostic oesophagogastroduodenoscopy (OGD) for dyspeptic symptoms are often receiving acid-suppression therapy that has not been discontinued prior to endoscopy, and this may reduce the diagnostic yield of endoscopy. The aim of this study was to compare the diagnostic yield of OGD in uncomplicated dyspepsia in patients receiving no medication, those receiving acid-suppression therapy, and those receiving nonsteroidal anti-inflammatory drugs (NSAIDs) at the time of endoscopy.

An audit of hospital admissions for acute upper gastrointestinal haemorrhage

A retrospective survey was made of all 189 patients admitted with acute upper gastrointestinal haemorrhage to the Belfast City Hospital in one year. The commonest single reason for admission was peptic ulcer disease, but this was lower than in other published series from the United Kingdom. Overall mortality was 4.8%. The majority of patients did not require either blood transfusion or surgery. There may be potential benefits of endoscopic haemostatic techniques to deal with this condition.

Human papillomavirus related head and neck cancer survival: A systematic review and meta-analysis

Human Papillomavirus (HPV) related oropharyngeal squamous cell carcinomas (OPSCCs) are reported to have improved prognosis and survival in comparison to other head and neck squamous cell cancers (HNSCCs). This systematic review and meta-analysis examines survival differences in HPV-positive HNSCC and OPSCC subtypes including tonsillar carcinoma in studies not previously investigated. Four electronic databases were searched from their inception till April 2011. A random effects meta-analysis was used to pool study estimates evaluating disease-specific (death from HNSCC), overall (all-cause mortality), progression-free and disease-free (recurrence free) survival outcomes in HPV-positive vs. HPV-negative HNSCCs. All statistical tests were two-sided. Forty-two studies were included. Patients with HPV-positive HNSCC had a 54% better overall survival compared to HPV-negative patients HR 0.46 (95% CI 0.37-0.57); the pooled HR for tonsillar cancer and OPSCC was 0.50 (95% CI 0.33-0.77) and HR 0.47 (95% CI 0.35-0.62) respectively. The pooled HR for disease specific survival was 0.28 (95% CI 0.19-0.40); similar effect sizes were found irrespective of the adjustment for confounders, HPV detection methods or study location. Both progression-free survival and disease-free survival were significantly improved in HPV-positive HNSCCs. HPV-positive HNSCCs and OPSCCs patients have a significantly lower disease specific mortality and are less likely to experience progression or recurrence of their cancer than HPV-negative patients; findings which have connotations for treatment selection in these patients.

On the filling factor of emitting material in the upper atmosphere of ε Eri (K2 V)

The emission measure distribution in the upper transition region and corona of e Eri is derived from observed emission-line fluxes. Theoretical emission measure distributions are calculated assuming that the radiation losses are balanced by the net conductive flux. We discuss how the area factor of the emitting regions as a function of temperature can be derived from a comparison between these emission measure distributions. It is found that the filling factor varies from ~0.2 in the mid-transition region to ~1.0 in the inner corona. The sensitivity of these results to the adopted ion fractions, the iron abundance and other parameters is discussed. The area factors found are qualitatively similar to the observed structure of the solar atmosphere, and can be used to constrain two-component models of the chromosphere. Given further observations, the method could be applied to investigate the trends in filling factors with indicators of stellar activity.

Human pose tracking in low dimensional space enhanced by limb correction

This paper proposes a two-level 3D human pose tracking method for a specific action captured by several cameras. The generation of pose estimates relies on fitting a 3D articulated model on a Visual Hull generated from the input images. First, an initial pose estimate is constrained by a low dimensional manifold learnt by Temporal Laplacian Eigenmaps. Then, an improved global pose is calculated by refining individual limb poses. The validation of our method uses a public standard dataset and demonstrates its accurate and computational efficiency. © 2011 IEEE.

Non-steroidal anti-inflammatory drug and aspirin use and the risk of head and neck cancer

Background: Evidence for non-steroidal anti-inflammatory drugs (NSAIDs) preventing head and neck cancer (HNC) is inconclusive; however, there is some suggestion that aspirin may exert a protective effect.

Methods: Using data from the United States National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, we examined the association between aspirin and ibuprofen use and HNC.

Results: Regular aspirin use was associated with a significant 22% reduction in HNC risk. No association was observed with regular ibuprofen use.

Conclusion: Aspirin may have potential as a chemopreventive agent for HNC, but further investigation is warranted.

Development and Validation of a Compact Thermal Model for an Aircraft Compartment

The development of accurate structural/thermal numerical models of complex systems, such as aircraft fuselage barrels, is often limited and determined by the smallest scales that need to be modelled. The development of reduced order models of the smallest scales and consequently their integration with higher level models can be a way to minimise the bottle neck present, while still having efficient, robust and accurate numerical models. In this paper a methodology on how to develop compact thermal fluid models (CTFMs) for compartments where mixed convection regimes are present is demonstrated. Detailed numerical simulations (CFD) have been developed for an aircraft crown compartment and validated against experimental data obtained from a 1:1 scale compartment rig. The crown compartment is defined as the confined area between the upper fuselage and the passenger cabin in a single aisle commercial aircraft. CFD results were utilised to extract average quantities (temperature and heat fluxes) and characteristic parameters (heat transfer coefficients) to generate CTFMs. The CTFMs have then been compared with the results obtained from the detailed models showing average errors for temperature predictions lower than 5%. This error can be deemed acceptable when compared to the nominal experimental error associated with the thermocouple measurements.

The CTFMs methodology developed allows to generate accurate reduced order models where accuracy is restricted to the region of Boundary Conditions applied. This limitation arises from the sensitivity of the internal flow structures to the applied boundary condition set. CTFMs thus generated can be then integrated in complex numerical modelling of whole fuselage sections.

Further steps in the development of an exhaustive methodology would be the implementation of a logic ruled based approach to extract directly from the CFD simulations numbers and positions of the nodes for the CTFM.

Relative Respiratory Syncytial Virus Cytopathogenesis in Upper and Lower Respiratory Tract Epithelium

Respiratory syncytial virus (RSV) is a major pathogen that primarily infects airway epithelium. Most infants suffer mild upper respiratory tract (URT) symptoms, while approximately one third progress to lower respiratory tract (LRT) involvement. Despite the ubiquity of URT infection, little is known about the relative cytopathogenesis of RSV infection in infant URT and LRT.

The lived experience of patients receiving radiotherapy for head and neck cancer: A literature review

It is estimated that 60% of patients diagnosed with head and neck cancer will receive radiotherapy at some stage in their disease trajectory. The aim of this literature review was to find and analyse papers pertaining to the lived experiences of patients with head and neck cancer receiving radiotherapy. The review identified a limited number of high-quality research papers focusing on this topic, with only 10 papers fitting the inclusion/exclusion criteria. The majority of the investigative studies were not generalisable owing to small sample sizes and many of them being conducted in only one centre. However, the findings do highlight and contribute to the understanding of the lived experiences of this patient group and provide some insight into the unique physical, social, and psychological difficulties they encounter as a result of their treatment. There appears to be a need for further high-level research into these patients, particularly focusing on the provision of support and information prior to, during, and following radiotherapy. Further attention needs to be paid to preparing patients for the slow recovery following radiotherapy. Interventional studies are also required to develop clinical guidelines and protocols that can assist health professionals in meeting the holistic needs of this patient group.

Observations of ubiquitous compressive waves in the Sun's chromosphere

The details of the mechanism(s) responsible for the observed heating and dynamics of the solar atmosphere still remain a mystery. Magnetohydrodynamic waves are thought to have a vital role in this process. Although it has been shown that incompressible waves are ubiquitous in off-limb solar atmospheric observations, their energy cannot be readily dissipated. Here we provide, for the first time, on-disk observation and identification of concurrent magnetohydrodynamic wave modes, both compressible and incompressible, in the solar chromosphere. The observed ubiquity and estimated energy flux associated with the detected magnetohydrodynamic waves suggest the chromosphere is a vast reservoir of wave energy with the potential to meet chromospheric and coronal heating requirements. We are also able to propose an upper bound on the flux of the observed wave energy that is able to reach the corona based on observational constraints, which has important implications for the suggested mechanism(s) for quiescent coronal heating. © 2012 Macmillan Publishers Limited. All rights reserved.