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https://www.readbyqxmd.com/read/28925314/effect-of-methylphenidate-on-visual-responses-in-the-superior-colliculus-in-the-anaesthetised-rat-role-of-cortical-activation
#1
L Hetherington, E J Dommett, A C Turner, T B Riley, J X Haensel, P G Overton
The mechanism of action of psychostimulant drugs in the treatment of Attention Deficit Hyperactivity Disorder is still largely unknown, although recent evidence suggests one possibility is that the drugs affect the superior colliculus (SC). We have previously demonstrated that systemically administered d-amphetamine attenuates/abolishes visual responses to wholefield light flashes in the superficial layers of the SC in anaesthetised rats, and the present study sought to extend this work to methylphenidate (MPH)...
September 1, 2017: Journal of Psychopharmacology
https://www.readbyqxmd.com/read/28923393/human-movement-analysis-the-soft-tissue-artefact-issue
#2
EDITORIAL
Valentina Camomilla, Raphaël Dumas, Aurelio Cappozzo
No abstract text is available yet for this article.
September 8, 2017: Journal of Biomechanics
https://www.readbyqxmd.com/read/28910720/study-of-the-influence-of-physical-chemical-and-biological-conditions-that-influence-the-deterioration-and-protection-of-underwater-cultural-heritage
#3
Manuel Bethencourt, Tomás Fernández-Montblanc, Alfredo Izquierdo, Manuel María González-Duarte, Cristian Muñoz-Mas
Two wrecks related to the Battle of Trafalgar (1805) were studied. Following the guidelines of the UNESCO-2001 Convention for the Protection of the Underwater Cultural Heritage, a holistic and interdisciplinary approach based on the development of four of the thirty-six Rules of this international agreement was applied. A non-destructive survey technique was developed to obtain information from the scattered cannons and anchors without altering their condition (Rule 4). The work performed provided information about the origin of both wrecks, the Fougueux and the Bucentaure, two ships of the line of the French Navy, and allowed to characterize the state of conservation at each site without jeopardizing their future conservation in the marine environment...
September 11, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28905393/pet-motion-correction-in-context-of-integrated-pet-mr-current-techniques-limitations-and-future-projections
#4
REVIEW
Ashley Gillman, Stephen Rose, Jye Smith, Paul Thomas, Nicholas Dowson
Patient motion is an important consideration in modern PET image reconstruction. Advances in PET technology mean motion has an increasingly important influence on resulting image quality. Motion-induced artefacts can have adverse effect on clinical outcomes, including missed diagnoses and oversized radiotherapy treatment volumes. This review aims to summarise the wide variety of motion correction techniques available in PET and combined PET/CT and PET/MR, with a focus on the latter. A general framework for the motion correction of PET images is presented, consisting of acquisition, modelling and correction stages...
September 14, 2017: Medical Physics
https://www.readbyqxmd.com/read/28902890/simultaneous-trimodal-pet-mr-eeg-imaging-do-eeg-caps-generate-artefacts-in-pet-images
#5
Ravichandran Rajkumar, Elena Rota Kops, Jörg Mauler, Lutz Tellmann, Christoph Lerche, Hans Herzog, N Jon Shah, Irene Neuner
Trimodal simultaneous acquisition of positron emission tomography (PET), magnetic resonance imaging (MRI), and electroencephalography (EEG) has become feasible due to the development of hybrid PET-MR scanners. To capture the temporal dynamics of neuronal activation on a millisecond-by-millisecond basis, an EEG system is appended to the quantitative high resolution PET-MR imaging modality already established in our institute. One of the major difficulties associated with the development of simultaneous trimodal acquisition is that the components traditionally used in each modality can cause interferences in its counterpart...
2017: PloS One
https://www.readbyqxmd.com/read/28901654/clinical-learning-environments-place-artefacts-and-rhythm
#6
Dale Sheehan, Tanisha Jowsey, Mariam Parwaiz, Mark Birch, Philippa Seaton, Susan Shaw, Alison Duggan, Tim Wilkinson
CONTEXT: Health care practitioners learn through experience in clinical environments in which supervision is a key component, but how that learning occurs outside the supervision relationship remains largely unknown. This study explores the environmental factors that inform and support workplace learning within a clinical environment. METHODS: An observational study drawing on ethnographic methods was undertaken in a general medicine ward. Observers paid attention to interactions among staff members that involved potential teaching and learning moments that occurred and were visible in the course of routine work...
October 2017: Medical Education
https://www.readbyqxmd.com/read/28900468/cancer-of-childhood-in-sub-saharan-africa
#7
REVIEW
Cristina Stefan, Freddie Bray, Jacques Ferlay, Biying Liu, D Maxwell Parkin
Measurement of incidence rates of childhood cancer in Africa is difficult. The study 'Cancer of Childhood in sub Saharan Africa' brings together results from 16 population-based registries which, as members of the African Cancer Registry Network (AFCRN), have been evaluated as achieving adequate coverage of their target population. The cancers are classified according to the third revision of the International Classification of Childhood Cancer (ICCC-3) and recorded rates in Africa are compared with those in childhood populations in the UK, France, and the USA...
2017: Ecancermedicalscience
https://www.readbyqxmd.com/read/28899210/competitive-action-video-game-players-display-rightward-error-bias-during-on-line-video-game-play
#8
Andrew J Roebuck, Aurora J B Dubnyk, David Cochran, Regan L Mandryk, John G Howland, Victoria Harms
Research in asymmetrical visuospatial attention has identified a leftward bias in the general population across a variety of measures including visual attention and line-bisection tasks. In addition, increases in rightward collisions, or bumping, during visuospatial navigation tasks have been demonstrated in real world and virtual environments. However, little research has investigated these biases beyond the laboratory. The present study uses a semi-naturalistic approach and the online video game streaming service Twitch to examine navigational errors and assaults as skilled action video game players (n = 60) compete in Counter Strike: Global Offensive...
September 12, 2017: Laterality
https://www.readbyqxmd.com/read/28895629/-novel-examination-procedures-for-the-assessment-of-retinal-artery-occlusion-by-oct-angiography
#9
Max Loidl, Christian Enders, Jens Ulrich Werner, Gerhard K Lang, Gabriele E Lang
Background Retinal artery occlusion (RAO) is the most common primary angiopathy of the retina. With an incidence of 0.01 - 0.15%, this it is a rather rare disease, but is associated with irreversible damage to the retina and a poor prognosis for visual acuity. Since the 1960s - when fluorescence angiography (FA) was developed -, there has been little change in diagnostic investigations. FA is still the standard procedure for the assessment of retinal artery occlusions. With the development of OCT angiography (OCT-A), new multimodal imaging procedures have become possible...
September 2017: Klinische Monatsblätter Für Augenheilkunde
https://www.readbyqxmd.com/read/28892874/mortality-from-multiple-sclerosis-in-british-military-personnel
#10
E Clare Harris, Keith T Palmer, Vanessa Cox, Andrew Darnton, John Osman, David Coggon
BACKGROUND: While analysing trends in occupational mortality in England and Wales, we noticed an unexpectedly elevated proportion of deaths from multiple sclerosis (MS) among men in the armed forces. AIMS: To document and explore possible explanations for the observed excess. METHODS: We analysed data on underlying cause of death and last full-time occupation for 3,688,916 deaths among men aged 20-74 years in England and Wales during 1979-2010, calculating proportional mortality ratios (PMRs) standardised for age...
August 1, 2017: Occupational Medicine
https://www.readbyqxmd.com/read/28891017/re-appraisal-of-estrogen-receptor-negative-progesterone-receptor-positive-er-pr-breast-cancer-phenotype-true-subtype-or-technical-artefact
#11
Niamh M Foley, J M Coll, A J Lowery, S O Hynes, M J Kerin, M Sheehan, C Brodie, K J Sweeney
Expression of the ER and PR receptors is routinely quantified in breast cancer as a predictive marker of response to hormonal therapy. Accurate determination of ER and PR status is critical to the optimal selection of patients for targeted therapy. The existence of an ER-/PR+ subtype is controversial, with debate centred on whether this represents a true phenotype or a technical artefact on immunohistochemistry (IHC). The aim of this study was to investigate the true incidence and clinico-pathological features of ER-/PR+ breast cancers in a tertiary referral symptomatic breast unit...
September 11, 2017: Pathology Oncology Research: POR
https://www.readbyqxmd.com/read/28887862/systolic-blood-pressure-targets-diastolic-j-curve-and-cuff-artefact-in-blood-pressure-measurement-a-note-of-caution
#12
J David Spence
There is good evidence that controlling hypertension reduces the risk of stroke and other cardiovascular consequences of hypertension. The recent Systolic Blood Pressure Intervention Trial (SPRINT) trial, stopped early because of a higher risk among participants randomized to the higher blood pressure target, will no doubt lead to calls for even lower pressures. Even among participants age ≥75, those randomized to a target systolic blood pressure (SBP) < 120 mmHg had a lower risk of stroke and cardiovascular events compared with a SBP target <140 mmHg[1]...
September 8, 2017: European Journal of Neurology: the Official Journal of the European Federation of Neurological Societies
https://www.readbyqxmd.com/read/28887553/insight-into-shark-magnetic-field-perception-from-empirical-observations
#13
James M Anderson, Tamrynn M Clegg, Luisa V M V Q Véras, Kim N Holland
Elasmobranch fishes are among a broad range of taxa believed to gain positional information and navigate using the earth's magnetic field, yet in sharks, much remains uncertain regarding the sensory receptors and pathways involved, or the exact nature of perceived stimuli. Captive sandbar sharks, Carcharhinus plumbeus were conditioned to respond to presentation of a magnetic stimulus by seeking out a target in anticipation of reward (food). Sharks in the study demonstrated strong responses to magnetic stimuli, making significantly more approaches to the target (p = < 0...
September 8, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28885606/an-overview-of-the-clinical-applications-of-optical-coherence-tomography-angiography
#14
REVIEW
A C S Tan, G S Tan, A K Denniston, P A Keane, M Ang, D Milea, U Chakravarthy, C M G Cheung
Optical coherence tomography angiography (OCTA) has emerged as a novel, non-invasive imaging modality that allows the detailed study of flow within the vascular structures of the eye. Compared to conventional dye angiography, OCTA can produce more detailed, higher resolution images of the vasculature without the added risk of dye injection. In our review, we discuss the advantages and disadvantages of this new technology in comparison to conventional dye angiography. We provide an overview of the current OCTA technology available, compare the various commercial OCTA machines technical specifications and discuss some future software improvements...
September 8, 2017: Eye
https://www.readbyqxmd.com/read/28883032/screening-for-atrial-fibrillation-in-hospitalised-geriatric-patients
#15
Rene Tavernier, Michael Wolf, Vikas Kataria, Tom Phlips, Ruben Huys, Philippe Taghji, Ruan Louw, Raf Van Hoeyweghen, Yves Vandekerckhove, Sébastien Knecht, Mattias Duytschaever
OBJECTIVES: To assess whether daily short-term rhythm strip recordings on top of routine clinical care could increase the atrial fibrillation (AF) detection rate in the hospitalised elderly. METHODS: A hand-held device storing a bipolar ECG during 1 min was used for daily rhythm recording in hospitalised elderly patients. RESULTS: During 2 months, all patients admitted to the Department of Geriatric Medicine were screened (n=327). Five patients refused to participate in the study and 70 patients were unable to hold the device due to severe mental (n=46) or motor impairment (n=24)...
September 7, 2017: Heart: Official Journal of the British Cardiac Society
https://www.readbyqxmd.com/read/28881239/comparing-in-situ-colorimetric-det-and-dgt-techniques-with-ex-situ-core-slicing-and-centrifugation-for-measuring-ferrous-iron-and-dissolved-sulfide-in-coastal-sediment-pore-waters
#16
Nadeeka Rathnayake Kankanamge, William W Bennett, Peter R Teasdale, Jianyin Huang, David T Welsh
In productive coastal sediments the separation between different biogeochemical zones (e.g. oxic, iron(III)-reducing and sulfate-reducing) may be on the scale of millimetres. Conventional measurement techniques simply cannot resolve changes in pore water solute concentrations over such small distances. The diffusive equilibration in thin films (DET) and the diffusive gradients in thin films (DGT) techniques allow in situ determination of pore water solute concentration profiles with one-dimensional profiles and/or two-dimensional distributions on the millimetre scale...
August 29, 2017: Chemosphere
https://www.readbyqxmd.com/read/28880161/unsupervised-segmentation-of-5d-hyperpolarized-carbon-13-mri-data-using-a-fuzzy-markov-random-field-model
#17
Ferdia A Gallagher, Charlie J Daniels
Hyperpolarized MRI with ¹³C-labelled compounds is an emerging clinical technique allowing in vivo metabolic processes to be characterized non-invasively. Accurate quantification of ¹³C data, both for clinical and research purposes, typically relies on the use of region-of-interest analysis to detect and compare regions of altered metabolism. However, it is not clear how this should be determined from the five-dimensional data produced and most standard methodologies are unable to exploit the multidimensional nature of the data...
September 4, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28878951/high-pitch-versus-conventional-cardiovascular-ct-in-patients-being-assessed-for-transcatheter-aortic-valve-implantation-a-real-world-appraisal
#18
Tevfik F Ismail, Emma Cheasty, Laurence King, Sahar Naaseri, Olga Lazoura, Natalie Gartland, Simon Padley, Michael B Rubens, Isabel Castellano, Edward D Nicol
OBJECTIVE: High-pitch protocols are increasingly used in cardiovascular CT assessment for transcatheter aortic valve implantation (TAVI), but the impact on diagnostic image quality is not known. METHODS: We reviewed 95 consecutive TAVI studies: 44 (46%) high-pitch and 51 (54%) standard-pitch. Single high-pitch scans were performed regardless of heart rate. For standard-pitch acquisitions, a separate CT-aortogram and CT-coronary angiogram were performed with prospective gating, unless heart rate was ≥70 beats/min, when retrospective gating was used...
2017: Open Heart
https://www.readbyqxmd.com/read/28878825/rna-sequence-data-normalization-through-in-silico-prediction-of-reference-genes-the-bacterial-response-to-dna-damage-as-case-study
#19
Bork A Berghoff, Torgny Karlsson, Thomas Källman, E Gerhart H Wagner, Manfred G Grabherr
BACKGROUND: Measuring how gene expression changes in the course of an experiment assesses how an organism responds on a molecular level. Sequencing of RNA molecules, and their subsequent quantification, aims to assess global gene expression changes on the RNA level (transcriptome). While advances in high-throughput RNA-sequencing (RNA-seq) technologies allow for inexpensive data generation, accurate post-processing and normalization across samples is required to eliminate any systematic noise introduced by the biochemical and/or technical processes...
2017: BioData Mining
https://www.readbyqxmd.com/read/28876236/auspex-a-graphical-tool-for-x-ray-diffraction-data-analysis
#20
Andrea Thorn, James Parkhurst, Paul Emsley, Robert A Nicholls, Melanie Vollmar, Gwyndaf Evans, Garib N Murshudov
In this paper, AUSPEX, a new software tool for experimental X-ray data analysis, is presented. Exploring the behaviour of diffraction intensities and the associated estimated uncertainties facilitates the discovery of underlying problems and can help users to improve their data acquisition and processing in order to obtain better structural models. The program enables users to inspect the distribution of observed intensities (or amplitudes) against resolution as well as the associated estimated uncertainties (sigmas)...
September 1, 2017: Acta Crystallographica. Section D, Structural Biology
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