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https://www.readbyqxmd.com/read/28917963/an-efficient-computational-fluid-particle-dynamics-method-to-predict-deposition-in-a-simplified-approximation-of-the-deep-lung
#1
P G Koullapis, P Hofemeier, J Sznitman, S C Kassinos
High-fidelity simulations of the complete airway tree are still largely beyond current computational capabilities. Towards large-scale simulations of the human lung, the current study introduces a numerical methodology to predict particle deposition in a simplified approximation of the deep lung during a full breathing cycle. The geometrical model employed consists of an idealised bronchial tree that represents generations 10 to 19 of the conducting zone and an heterogeneous acinar model created using a space-filling algorithm...
September 13, 2017: European Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28915737/periodic-layers-of-a-dodecagonal-quasicrystal-and-a-floating-hexagonal-crystal-in-sedimentation-diffusion-equilibria-of-colloids
#2
Harini Pattabhiraman, Marjolein Dijkstra
We investigate the behaviour of a system of colloidal particles interacting with a hard-core and a repulsive square shoulder potential under the influence of a gravitational field using event-driven Brownian dynamics simulations. We use a fixed square shoulder diameter equal to 1.4 times the hard-core diameter of the colloids, for which we have previously calculated the equilibrium phase diagram considering two-dimensional disks [H. Pattabhiraman et al., J. Chem. Phys. 143, 164905 (2015) and H. Pattabhiraman and M...
September 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28910743/is-scena-a-good-approach-for-side-stream-integrated-treatment-from-an-environmental-and-economic-point-of-view
#3
Stefano Longo, Nicola Frison, Daniele Renzi, Francesco Fatone, Almudena Hospido
The environmental and economic benefits and burdens of including the first Short Cut Enhanced Nutrient Abatement (SCENA) into a real municipal wastewater treatment plant were evaluated using life cycle assessment (LCA) and life cycle cost (LCC). The implications of accomplishing nitrogen (N) removal and phosphorus (P) recovery via nitrite in the side stream were assessed taking into account the actual effluent quality improvement, the changes in the electricity and chemical consumption, N2O, CO2 and CH4 emissions and the effects of land application of biosolids, among others...
September 6, 2017: Water Research
https://www.readbyqxmd.com/read/28910670/mental-imagery-of-gravitational-motion
#4
Silvio Gravano, Myrka Zago, Francesco Lacquaniti
There is considerable evidence that gravitational acceleration is taken into account in the interaction with falling targets through an internal model of Earth gravity. Here we asked whether this internal model is accessed also when target motion is imagined rather than real. In the main experiments, naïve participants grasped an imaginary ball, threw it against the ceiling, and caught it on rebound. In different blocks of trials, they had to imagine that the ball moved under terrestrial gravity (1g condition) or under microgravity (0g) as during a space flight...
August 9, 2017: Cortex; a Journal Devoted to the Study of the Nervous System and Behavior
https://www.readbyqxmd.com/read/28903848/prosthetic-rehabilitation-of-a-partially-edentulous-patient-with-maxillary-acquired-defect-by-a-two-piece-hollow-bulb-obturator-using-a-dentogenic-concept
#5
Poonam R Kulkarni, Rahul S Kulkarni, Rupal J Shah, Kavita Maru
Patients may face functional, aesthetic, and social distress because of the palatal defects. Prosthetic rehabilitation of maxillectomy or developmental defect can be challenging for prosthodontists. Prognosis of the prosthetic appliances can be affected not only by patients' own ability to adapt to the prosthesis but also by the factors like the remaining teeth, bony structure, and existing mucosa. Maxillary defects are usually developed by surgical intercession of the benign or malignant conditions and trauma cases...
August 2017: Journal of the College of Physicians and Surgeons—Pakistan: JCPSP
https://www.readbyqxmd.com/read/28884775/modeling-of-active-swimmer-suspensions-and-their-interactions-with-the-environment
#6
REVIEW
Nikhil Desai, Arezoo M Ardekani
In this article, we review mathematical models used to study the behaviour of suspensions of micro-swimmers and the accompanying biophysical phenomena, with specific focus on stimulus response. The methods discussed encompass a range of interactions exhibited by the micro-swimmers; including passive hydrodynamic (gyrotaxis) and gravitational (gravitaxis) effects, and active responses to chemical cues (chemotaxis) and light intensities (phototaxis). We introduce the simplest models first, and then build towards more sophisticated recent developments, in the process, identifying the limitations of the former and the new results obtained by the latter...
September 8, 2017: Soft Matter
https://www.readbyqxmd.com/read/28884596/3d-map-modelling-for-the-melting-points-prediction-of-intumescent-flame-retardant-coatings
#7
A S Korotkov, M Gravit
The applicability of 3D map modelling for melting point prediction was studied. The melting points in the ammonium polyphosphate-pentaerythritol-melamine chemical system of intumescent flame-retardant coatings over a wide range of concentrations were collected. The ternary diagram (triangle) of the melting points was plotted and an approximated 3D map was built for the range 205-345°C. The present work contains the thermal data for the observed ternary system and provides a new graphic system for making predictions for intumescent flame-retardant coatings...
September 8, 2017: SAR and QSAR in Environmental Research
https://www.readbyqxmd.com/read/28880282/quantum-gravity-quantum-effects-in-the-gravitational-field
#8
Sabine Hossenfelder, Chiara Marletto, Vlatko Vedral
No abstract text is available yet for this article.
September 6, 2017: Nature
https://www.readbyqxmd.com/read/28879228/thermodiffusion-in-multicomponent-n-alkane-mixtures
#9
Guillaume Galliero, Henri Bataller, Jean-Patrick Bazile, Joseph Diaz, Fabrizio Croccolo, Hai Hoang, Romain Vermorel, Pierre-Arnaud Artola, Bernard Rousseau, Velisa Vesovic, M Mounir Bou-Ali, José M Ortiz de Zárate, Shenghua Xu, Ke Zhang, François Montel, Antonio Verga, Olivier Minster
Compositional grading within a mixture has a strong impact on the evaluation of the pre-exploitation distribution of hydrocarbons in underground layers and sediments. Thermodiffusion, which leads to a partial diffusive separation of species in a mixture due to the geothermal gradient, is thought to play an important role in determining the distribution of species in a reservoir. However, despite recent progress, thermodiffusion is still difficult to measure and model in multicomponent mixtures. In this work, we report on experimental investigations of the thermodiffusion of multicomponent n-alkane mixtures at pressure above 30 MPa...
2017: NPJ Microgravity
https://www.readbyqxmd.com/read/28873673/colloidal-properties-of-sodium-caseinate-stabilized-nanoemulsions-prepared-by-a-combination-of-a-high-energy-homogenization-and-evaporative-ripening-methods
#10
J M Montes de Oca-Ávalos, R J Candal, M L Herrera
Nanoemulsions stabilized by sodium caseinate (NaCas) were prepared using a combination of a high-energy homogenization and evaporative ripening methods. The effects of protein concentration and sucrose addition on physical properties were analyzed by dynamic light scattering (DLS), Turbiscan analysis, confocal laser scanning microscopy (CLSM) and small angle X-ray scattering (SAXS). Droplets sizes were smaller (~100nm in diameter) than the ones obtained by other methods (200 to 2000nm in diameter). The stability behavior was also different...
October 2017: Food Research International
https://www.readbyqxmd.com/read/28871155/long-distance-impact-of-iceland-plume-on-norway-s-rifted-margin
#11
Alexander Koptev, Sierd Cloetingh, Evgueni Burov, Thomas François, Taras Gerya
Results of a 3D modeling study inspired by recent seismic tomography of the Northern Atlantic mantle suggest that a complex pattern of hot mantle distribution with long horizontal flows originating from the Iceland mantle plume has been the norm in the geological past. In the Northern Atlantic the Iceland plume has a strong long-distance impact on intraplate deformation affecting both onshore and offshore parts of Norway's rifted margin. As a result, this margin is characterized by large magnitude differential topography sustained over at least several tens of Myr...
September 4, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28868355/stability-of-gene-expression-in-human-t-cells-in-different-gravity-environments-is-clustered-in-chromosomal-region-11p15-4
#12
Cora S Thiel, Andreas Huge, Swantje Hauschild, Svantje Tauber, Beatrice A Lauber, Jennifer Polzer, Katrin Paulsen, Hartwin Lier, Frank Engelmann, Burkhard Schmitz, Andreas Schütte, Liliana E Layer, Oliver Ullrich
In the last decades, a plethora of in vitro studies with living human cells contributed a vast amount of knowledge about cellular and molecular effects of microgravity. Previous studies focused mostly on the identification of gravity-responsive genes, whereas a multi-platform analysis at an integrative level, which specifically evaluates the extent and robustness of transcriptional response to an altered gravity environment was not performed so far. Therefore, we investigated the stability of gene expression response in non-activated human Jurkat T lymphocytic cells in different gravity environments through the combination of parabolic flights with a suborbital ballistic rocket and 2D clinostat and centrifuge experiments, using strict controls for excluding all possible other factors of influence...
2017: NPJ Microgravity
https://www.readbyqxmd.com/read/28867771/gps-satellite-orbit-prediction-at-user-end-for-real-time-ppp-system
#13
Hongzhou Yang, Yang Gao
This paper proposed the high-precision satellite orbit prediction process at the user end for the real-time precise point positioning (PPP) system. Firstly, the structure of a new real-time PPP system will be briefly introduced in the paper. Then, the generation of satellite initial parameters (IP) at the sever end will be discussed, which includes the satellite position, velocity, and the solar radiation pressure (SRP) parameters for each satellite. After that, the method for orbit prediction at the user end, with dynamic models including the Earth's gravitational force, lunar gravitational force, solar gravitational force, and the SRP, are presented...
August 30, 2017: Sensors
https://www.readbyqxmd.com/read/28863518/helical-paths-gravitaxis-and-separation-phenomena-for-mass-anisotropic-self-propelling-colloids-experiment-versus-theory
#14
Andrew I Campbell, Raphael Wittkowski, Borge Ten Hagen, Hartmut Löwen, Stephen J Ebbens
The self-propulsion mechanism of active colloidal particles often generates not only translational but also rotational motion. For particles with an anisotropic mass density under gravity, the motion is usually influenced by a downwards oriented force and an aligning torque. Here we study the trajectories of self-propelled bottom-heavy Janus particles in three spatial dimensions both in experiments and by theory. For a sufficiently large mass anisotropy, the particles typically move along helical trajectories whose axis is oriented either parallel or antiparallel to the direction of gravity (i...
August 28, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28861024/gravity-cues-embedded-in-the-kinematics-of-human-motion-are-detected-in-form-from-motion-areas-of-the-visual-system-and-in-motor-related-areas
#15
Fabien Cignetti, Pierre-Yves Chabeauti, Jasmine Menant, Jean-Luc J J Anton, Christina Schmitz, Marianne Vaugoyeau, Christine Assaiante
The present study investigated the cortical areas engaged in the perception of graviceptive information embedded in biological motion (BM). To this end, functional magnetic resonance imaging was used to assess the cortical areas active during the observation of human movements performed under normogravity and microgravity (parabolic flight). Movements were defined by motion cues alone using point-light displays. We found that gravity modulated the activation of a restricted set of regions of the network subtending BM perception, including form-from-motion areas of the visual system (kinetic occipital region, lingual gyrus, cuneus) and motor-related areas (primary motor and somatosensory cortices)...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28860333/using-hyperpolarized-129-xe-mri-to-quantify-regional-gas-transfer-in-idiopathic-pulmonary-fibrosis
#16
Jennifer M Wang, Scott H Robertson, Ziyi Wang, Mu He, Rohan S Virgincar, Geoffry M Schrank, Rose Marie Smigla, Thomas G O'Riordan, John Sundy, Lukas Ebner, Craig R Rackley, Page McAdams, Bastiaan Driehuys
BACKGROUND: Assessing functional impairment, therapeutic response and disease progression in patients with idiopathic pulmonary fibrosis (IPF) continues to be challenging. Hyperpolarized (129)Xe MRI can address this gap through its unique capability to image gas transfer three-dimensionally from airspaces to interstitial barrier tissues to red blood cells (RBCs). This must be validated by testing the degree to which it correlates with pulmonary function tests (PFTs) and CT scores, and its spatial distribution reflects known physiology and patterns of disease...
August 31, 2017: Thorax
https://www.readbyqxmd.com/read/28858317/fast-automated-analysis-of-strong-gravitational-lenses-with-convolutional-neural-networks
#17
Yashar D Hezaveh, Laurence Perreault Levasseur, Philip J Marshall
Quantifying image distortions caused by strong gravitational lensing-the formation of multiple images of distant sources due to the deflection of their light by the gravity of intervening structures-and estimating the corresponding matter distribution of these structures (the 'gravitational lens') has primarily been performed using maximum likelihood modelling of observations. This procedure is typically time- and resource-consuming, requiring sophisticated lensing codes, several data preparation steps, and finding the maximum likelihood model parameters in a computationally expensive process with downhill optimizers...
August 30, 2017: Nature
https://www.readbyqxmd.com/read/28857747/investigation-of-cerebral-venous-outflow-in-microgravity
#18
Angelo Taibi, Giacomo Gadda, Mauro Gambaccini, Erica Menegatti, Francesco Sisini, Paolo Zamboni
The gravitational gradient is the major component to face when considering the physiology of venous return and there is a growing interest in understanding the mechanisms ensuring the heart filling in the absence of gravity for astronauts who perform long-term space missions. The purpose of the Drain Brain project was to monitor the cerebral venous outflow of the crew member during an experiment on the International Space Station, so as to study the compensatory mechanisms that facilitate this essential physiological action in subjects living in a microgravity environment...
August 31, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28854390/particle-deposition-in-tracheobronchial-airways-of-an-infant-child-and-adult
#19
Qihong Deng, Cuiyun Ou, Jiao Chen, Yuguang Xiang
BACKGROUND: Particle deposition in human airways is important for assessing both health effects of inhaled particles and therapeutic efficacy of inhaled drug aerosols, but is not well understood for infants and children. OBJECTIVE: We investigate particle deposition in infants and children by using computational fluid dynamics (CFD), and compare this with particle deposition in adults. METHODS: We chose three population age groups: 7-month infant, 4-year old child, and 20-year old adult...
August 27, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28854273/high-resolution-imaging-of-the-mitral-valve-in-the-natural-state-with-7-tesla-mri
#20
Sam E Stephens, Serguei Liachenko, Neil B Ingels, Jonathan F Wenk, Morten O Jensen
Imaging techniques of the mitral valve have improved tremendously during the last decade, but challenges persist. The delicate changes in annulus shape and papillary muscle position throughout the cardiac cycle have significant impact on the stress distribution in the leaflets and chords, thus preservation of anatomically accurate positioning is critical. The aim of this study was to develop an in vitro method and apparatus for obtaining high-resolution 3D MRI images of porcine mitral valves in both the diastolic and systolic configurations with physiologically appropriate annular shape, papillary muscle positions and orientations, specific to the heart from which the valve was harvested...
2017: PloS One
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