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https://www.readbyqxmd.com/read/29136287/quantification-of-mri-visibility-and-artefacts-at-3t-of-liquid-fiducial-marker-in-a-pancreas-tissue-mimicking-phantom
#1
Sergej Schneider, Rasmus Irming Jølck, Esther Gera Cornelia Troost, Aswin Louis Hoffmann
PURPOSE: X-ray based position verification of the target volume in image-guided radiation therapy (IGRT) of patients with pancreatic ductal adenocarcinoma (PDAC) is currently performed on solid fiducial markers that are implanted under endoscopic ultrasonography. A new biodegradable liquid fiducial marker has recently been introduced. To assess its potential use for magnetic resonance imaging (MRI) guided photon or proton radiotherapy of PDAC, the MRI visibility and artefacts of this marker were quantified and compared against solid gold markers...
November 14, 2017: Medical Physics
https://www.readbyqxmd.com/read/29134751/cortical-hemispheric-asymmetries-are-present-at-young-ages-and-further-develop-into-adolescence
#2
Hiroshi Yamazaki, Vijayalakshmi Easwar, Melissa Jane Polonenko, Salima Jiwani, Daniel D E Wong, Blake Croll Papsin, Karen Ann Gordon
Specialization of the auditory cortices for pure tone listening may develop with age. In adults, the right hemisphere dominates when listening to pure tones and music; we thus hypothesized that (a) asymmetric function between auditory cortices increases with age and (b) this development is specific to tonal rather than broadband/non-tonal stimuli. Cortical responses to tone-bursts and broadband click-trains were recorded by multichannel electroencephalography in young children (5.1 ± 0.8 years old) and adolescents (15...
November 13, 2017: Human Brain Mapping
https://www.readbyqxmd.com/read/29133442/a-probabilistic-framework-for-identifying-biosignatures-using-pathway-complexity
#3
Stuart M Marshall, Alastair R G Murray, Leroy Cronin
One thing that discriminates living things from inanimate matter is their ability to generate similarly complex or non-random structures in a large abundance. From DNA sequences to folded protein structures, living cells, microbial communities and multicellular structures, the material configurations in biology can easily be distinguished from non-living material assemblies. Many complex artefacts, from ordinary bioproducts to human tools, though they are not living things, are ultimately produced by biological processes-whether those processes occur at the scale of cells or societies, they are the consequences of living systems...
December 28, 2017: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29132245/radial-vs-coccygeal-artery-doppler-blood-pressure-measurement-in-conscious-cats
#4
Florian K Zeugswetter, Alexander Tichy, Katharina Weber
Objectives The aims of the study were to compare the results of systolic blood pressure (SBP) measurements at the radial and coccygeal artery by Doppler ultrasonography and to assess the impact of gender, age, body weight, body condition score (BCS) and stress score on disagreements. Methods Eighty cats were included in this prospective, block randomised crossover trial. Blood pressure measurements were performed at home, during hospitalisation or in a local animal shelter by a single trained observer according to the latest ISFM consensus guidelines...
November 1, 2017: Journal of Feline Medicine and Surgery
https://www.readbyqxmd.com/read/29122887/a-reference-based-protein-degradation-assay-without-global-translation-inhibitors
#5
Jang-Hyun Oh, Shun-Jia Chen, Alexander Varshavsky
Although it is widely appreciated that the use of global translation inhibitors, such as cycloheximide, in protein degradation assays may result in artefacts, these inhibitors continue to be employed, owing to the absence of robust alternatives. We describe here the promoter reference technique (PRT), an assay for protein degradation with two advantageous features: a reference protein and a gene-specific inhibition of translation. In PRT assays, one measures, during a chase, the ratio of a test protein to a long-lived reference protein, a dihydrofolate reductase (DHFR)...
November 9, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/29122647/an-automatic-system-for-the-comprehensive-retrospective-analysis-of-cardiac-rhythms-in-resuscitation-episodes
#6
Ali Bahrami Rad, Trygve Eftestøl, Unai Irusta, Jan Terje Kvaløy, Lars Wik, Jo Kramer-Johansen, Aggelos K Katsaggelos, Kjersti Engan
AIM: An automatic resuscitation rhythm annotator (ARA) would facilitate and enhance retrospective analysis of resuscitation data, contributing to a better understanding of the interplay between therapy and patient response. The objective of this study was to define, implement, and demonstrate an ARA architecture for complete resuscitation episodes, including chest compression pauses (CC-pauses) and chest compression intervals (CC-intervals). METHODS: We analyzed 126...
November 6, 2017: Resuscitation
https://www.readbyqxmd.com/read/29122452/estimated-landmark-calibration-of-biomechanical-models-for-inverse-kinematics
#7
Ursula Trinler, Richard Baker
Inverse kinematics is emerging as the optimal method in movement analysis to fit a multi-segment biomechanical model to experimental marker positions. A key part of this process is calibrating the model to the dimensions of the individual being analysed which requires scaling of the model, pose estimation and localisation of tracking markers within the relevant segment coordinate systems. The aim of this study is to propose a generic technique for this process and test a specific application to the OpenSim model Gait2392...
November 6, 2017: Medical Engineering & Physics
https://www.readbyqxmd.com/read/29120867/quantifying-the-ultrastructure-of-carotid-arteries-using-high-resolution-micro-diffusion-tensor-imaging-comparison-of-intact-versus-open-cut-tissue
#8
Syed Salman Shahid, Robert T Gaul, Christian Kerskens, Vittoria Flamini, Caitríona Lally
Diffusion magnetic resonance imaging (dMRI) can provide insights into the microstructure of intact arterial tissue. The current study employed high magnetic field MRI to obtain ultra-high resolution dMRI at an isotropic voxel resolution of 117 µm(3) in less than 2 h of scan time. A parameter selective single shell (128 directions) diffusion-encoding scheme based on Stejskel-Tanner sequence with echo-planar imaging (EPI) readout was used. EPI segmentation was used to reduce the echo time (TE) and to minimise the susceptibility-induced artefacts...
November 9, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/29120662/comparison-of-mri-visualisation-between-linearly-placed-iron-containing-and-non-iron-containing-fiducial-markers-for-prostate-radiotherapy
#9
Osamu Tanaka, Hisao Komeda, Masayoshi Tamaki, Kensaku Seike, Shota Fujimoto, Eiichi Yama, Shigeki Hirose, Masayuki Matsuo
OBJECTIVE: Visualising the gold marker (GM) in CT and MRI is critical, especially for registration in high-precision radiotherapy. GM sizes vary. Large markers are easily visualised in MRI. Small GMs show fewer artefacts in CT but are harder to detect in MRI because the signal is influenced by metal in MRI. Therefore, we compared MRI visualisation between linearly placed new iron-containing marker and non-iron containing marker. METHODS: Twenty-seven patients underwent CT/MRI fusion-based intensity-modulated radiotherapy...
November 9, 2017: British Journal of Radiology
https://www.readbyqxmd.com/read/29119924/deaths-in-the-lesbian-gay-bisexual-and-transgender-united-kingdom-communities-associated-with-ghb-and-precursors
#10
John M Corkery, Barbara Loi, Hugh Claridge, Christine Goodair, Fabrizio Schifano
Background Misuse of gammahydroxybutrate (GHB) and its prodrugs gammabutyrolactone (GBL) and 1,4 butanediol (1,4-BD) has increased greatly since the early 1990s, particularly amongst lesbian, gay, bisexual and transgender (LGBT) individuals in recreational and sexual settings, e.g. 'chemsex'. Objective and method This paper presents an overview of GHB pharmacotoxicology and provides analyses of cases in the LGBT population associated with use of these substances extracted from the UK's National Programme on Substance Abuse Deaths database, to which notification is voluntary...
November 8, 2017: Current Drug Metabolism
https://www.readbyqxmd.com/read/29119455/ct-brain-artefact-due-to-air-bubbles-in-the-oil-cooling-system-characteristic-band-like-configuration-on-sagittal-reformatted-image
#11
Simon Sin Man Wong, James Siu Wai Cheung, Tom Wai Kin Lee, Chris Siu Chun Tsai, Alex Wing Hung Ng
PURPOSE: To retrospectively review the imaging characteristics of CT artefacts due to air bubbles within the oil cooling system of the X-ray tube housing. MATERIALS AND METHODS: Air bubbles were introduced into the oil cooling system of the X-ray tube housing during tube replacement in one of the CT scanners in the authors' institution. All 126 CT brain studies performed in this period were retrospectively reviewed. One hundred and four studies were negative for artefacts...
November 8, 2017: Japanese Journal of Radiology
https://www.readbyqxmd.com/read/29115751/using-videoed-workshops-in-interdisciplinary-research-with-people-who-have-disabilities
#12
Fiona Timmins, Pearl O'rourke, Annamaria Bagnasco, Bernard Timmins, Ray Ekins, Siobhan Long, Giuseppe Aleo, Loredana Sasso
BACKGROUND: Internationally, interdisciplinary research is advocated in healthcare. Such research receives great respect, particularly from funding bodies, which expect innovations in healthcare to emerge from a whole team rather than a single discipline. However, little guidance exists about the process and structures for such research. AIM: To explore and explain the use of videoed workshops and mixed-media artefacts to collect data, and explore the benefits and challenges for interdisciplinary healthcare research...
September 19, 2017: Nurse Researcher
https://www.readbyqxmd.com/read/29113934/validating-ehr-clinical-models-using-ontology-patterns
#13
Catalina Martínez-Costa, Stefan Schulz
Clinical models are artefacts that specify how information is structured in electronic health records (EHRs). However, the makeup of clinical models is not guided by any formal constraint beyond a semantically vague information model. We address this gap by advocating ontology design patterns as a mechanism that makes the semantics of clinical models explicit. This paper demonstrates how ontology design patterns can validate existing clinical models using SHACL. Based on the Clinical Information Modelling Initiative (CIMI), we show how ontology patterns detect both modeling and terminology binding errors in CIMI models...
November 4, 2017: Journal of Biomedical Informatics
https://www.readbyqxmd.com/read/29110456/general-two-dimensional-absorption-mode-j-resolved-nmr-spectroscopy
#14
Yuqing Huang, Yu Yang, Shuhui Cai, Zhiwei Chen, Haolin Zhan, Chen Li, Chunhua Tan, Zhong Chen
Two-dimensional (2D) J-resolved NMR technique offers a natural solution for disentangling complex mixtures that suffer from crowded spectra in 1D NMR. The applicability of classical 2D J-resolved spectroscopy is inevitably limited by phase-twist lineshapes and strong coupling artifacts. Here, a general and robust NMR method is proposed to record 2D absorption-mode J-resolved spectra in rapid acquisition manner. This method can also reduce the impact of strong coupling artifacts, thus achieving full considerations for applications...
November 15, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29107950/a-new-method-to-determine-cortical-bone-thickness-in-ct-images-using-a-hybrid-approach-of-parametric-profile-representation-and-local-adaptive-thresholds-accuracy-results
#15
Oleg Museyko, Bastian Gerner, Klaus Engelke
MOTIVATION: Cortical bone is an important contributor to bone strength and is pivotal to understand the etiology of osteoporotic fractures and the specific mechanisms of antiosteoporotic treatment regimen. 3D computed tomography (CT) can be used to measure cortical thickness, density, and mass in the proximal femur, lumbar vertebrae, and distal forearm. However, the spatial resolution of clinical whole body CT scanners is limited by radiation exposure; partial volume artefacts severely impair the accurate assessment of cortical parameters, in particular in locations where the cortex is thin such as in the lumbar vertebral bodies or in the femoral neck...
2017: PloS One
https://www.readbyqxmd.com/read/29101010/mate-choice-could-be-random-in-female-rats-rattus-norvegicus
#16
Olivia Le Moëne, Eelke M Snoeren
Female mate choice is often investigated in terms of reproductive success in order to understand how male characteristics contribute to sexual attractiveness. Previous studies have found that females rats prefer mating with their first encounter rather than males visited subsequently, suggesting that the rewarding value of this first encounter is enough to reinforce mating with the first partner. Using a multiple chambers paradigm, we allowed female rats to copulate freely with three males placed each in a different chamber...
November 1, 2017: Physiology & Behavior
https://www.readbyqxmd.com/read/29100697/automated-reference-free-local-error-assessment-of-multimodal-deformable-image-registration-for-radiotherapy-in-the-head-and-neck
#17
Michael G Nix, Robin J D Prestwich, Richard Speight
BACKGROUND: Head and neck MR-CT deformable image registration (DIR) for radiotherapy planning is hindered by the lack of both ground-truth and per-patient accuracy assessment methods. This study assesses novel post-registration reference-free error assessment algorithms, based on local rigid re-registration of native and pseudomodality images. METHODS: Head and neck MR obtained in and out of the treatment position underwent DIR to planning CT. Block-wise mutual information (b-MI) and pseudomodality mutual information (b-pmMI) algorithms were validated against applied rotations and translations...
October 31, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/29099719/methodology-for-extraction-of-space-charge-density-profiles-at-nanoscale-from-kelvin-probe-force-microscopy-measurements
#18
Christina Villeneuve-Faure, Laurent Boudou, Kremena Makasheva, Gilbert Teyssedre
To understand the physical phenomena occurring at metal/dielectric interfaces, determination of the charge density profile at nanoscale is crucial. To deal with this issue, charges were injected applying a DC voltage on lateral Al-electrodes embedded in SiNx thin dielectric layer. The surface potential induced by the injected charges was probed by Kelvin Probe Force Microscopy (KPFM). It is found that the KPFM frequency mode is better adapted method to probe accurately the charge profile. To extract the charge density profile from the surface potential two numerical approaches based on solution of the Poisson's equation for electrostatic were investigated: Second Derivative Model (SDM) method, already reported in the literature, and a new 2D-method based on Finite Element Method (FEM)...
November 3, 2017: Nanotechnology
https://www.readbyqxmd.com/read/29096216/rhythmic-eeg-patterns-in-extremely-preterm-infants-classification-and-association-with-brain-injury-and-outcome
#19
Lauren C Weeke, Inge M van Ooijen, Floris Groenendaal, Alexander C van Huffelen, Ingrid C van Haastert, Carolien van Stam, Manon J Benders, Mona C Toet, Lena Hellström-Westas, Linda S de Vries
OBJECTIVE: Classify rhythmic EEG patterns in extremely preterm infants and relate these to brain injury and outcome. METHODS: Retrospective analysis of 77 infants born <28 weeks gestational age (GA) who had a 2-channel EEG during the first 72 h after birth. Patterns detected by the BrainZ seizure detection algorithm were categorized: ictal discharges, periodic epileptiform discharges (PEDs) and other waveforms. Brain injury was assessed with sequential cranial ultrasound (cUS) and MRI at term-equivalent age...
October 3, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/29095959/wanted-dead-or-alive-using-metabarcoding-of-environmental-dna-and-rna-to-distinguish-living-assemblages-for-biosecurity-applications
#20
Xavier Pochon, Anastasija Zaiko, Lauren M Fletcher, Olivier Laroche, Susanna A Wood
High-throughput sequencing metabarcoding studies in marine biosecurity have largely focused on targeting environmental DNA (eDNA). DNA can persist extracellularly in the environment, making discrimination of living organisms difficult. In this study, bilge water samples (i.e., water accumulating on-board a vessel during transit) were collected from 15 small recreational and commercial vessels. eDNA and eRNA molecules were co-extracted and the V4 region of the 18S ribosomal RNA gene targeted for metabarcoding...
2017: PloS One
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