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https://www.readbyqxmd.com/read/28431980/shear-stress-alterations-in-the-celiac-trunk-of-patients-with-a-continuous-flow-left-ventricular-assist-device-as-shown-by-in-silico-and-in-vitro-flow-analyses
#1
Francesco Scardulla, Salvatore Pasta, Leonardo D'Acquisto, Sergio Sciacca, Valentina Agnese, Christian Vergara, Alfio Quarteroni, Francesco Clemenza, Diego Bellavia, Michele Pilato
BACKGROUND: The use of left ventricular assist devices (LVADs) to treat advanced cardiac heart failure is constantly increasing, although this device leads to high risk for gastrointestinal bleeding. METHODS: Using in-silico flow analysis, we quantified hemodynamic alterations due to continuous-flow LVAD (HeartWare, Inc., Framingham, MA) in the celiac trunk and major branches of the abdominal aorta, and then explored the relationship between wall shear stress (WSS) and celiac trunk orientation...
March 24, 2017: Journal of Heart and Lung Transplantation
https://www.readbyqxmd.com/read/28431428/computational-and-in-vitro-experimental-investigation-of-intrathecal-drug-distribution-parametric-study-of-the-effect-of-injection-volume-cerebrospinal-fluid-pulsatility-and-drug-uptake
#2
Kevin M Tangen, Roxanne Leval, Ankit I Mehta, Andreas A Linninger
BACKGROUND: Intrathecal drug delivery is an attractive option to circumvent the blood-brain barrier for pain management through its increased efficacy of pain relief, reduction in adverse side effects, and cost-effectiveness. Unfortunately, there are limited guidelines for physicians to choose infusion or drug pump settings to administer therapeutic doses to specific regions of the spine or the brain. Although empiric trialing of intrathecal drugs is critical to determine the sustained side effects, currently there is no inexpensive in vitro method to guide the selection of spinal drug delivery parameters...
May 2017: Anesthesia and Analgesia
https://www.readbyqxmd.com/read/28430110/viscosity-of-a-sheared-correlated-near-critical-model-fluid-in-confinement
#3
Christian Rohwer, Andrea Gambassi, Matthias Kruger
Second-order phase transitions are characterized by a divergence of the spatial correlation length of the order parameter fluctuations. For confined systems, this is known to lead to remarkable equilibrium physical phenomena, including finite-size effects and critical Casimir forces. We explore here some non-equilibrium aspects of these effects in the stationary state resulting from the action of external forces: by analyzing a model of a correlated fluid under shear, spatially confined by two parallel plates, we study the resulting viscosity within the setting of (Gaussian) Landau-Ginzburg theory...
April 21, 2017: Journal of Physics. Condensed Matter: An Institute of Physics Journal
https://www.readbyqxmd.com/read/28426333/existence-and-uniqueness-for-a-coupled-pde-model-for-motor-induced-microtubule-organization
#4
Thomas Hillen, Diana White, Gerda de Vries, Adriana Dawes
Microtubules (MTs) are protein filaments that provide structure to the cytoskeleton of cells and a platform for the movement of intracellular substances. The spatial organization of MTs is crucial for a cell's form and function. MTs interact with a class of proteins called motor proteins that can transport and position individual filaments, thus contributing to overall organization. In this paper, we study the mathematical properties of a coupled partial differential equation (PDE) model, introduced by White et al...
April 20, 2017: Journal of Biological Dynamics
https://www.readbyqxmd.com/read/28421855/midterm-outcomes-after-infrapopliteal-interventions-in-patients-with-critical-limb-ischemia-based-on-the-tasc-ii-classification-of-below-the-knee-arteries
#5
Gagan D Singh, Ellen K Brinza, Justin Hildebrand, Stephen W Waldo, T Raymond Foley, John R Laird, Ehrin J Armstrong
PURPOSE: To analyze the relationship between the new TransAtlantic Inter-Society Consensus (TASC II) infrapopliteal classification and limb outcomes among patients with critical limb ischemia (CLI). METHODS: A single-center retrospective study was performed on 166 consecutive CLI patients (mean age 71 years; 113 men) undergoing endovascular treatment of 244 infrapopliteal lesions from 2006 to 2013. Patient, procedural, angiographic, and limb outcomes were compared for the new TASC A/B vs C/D classification for infrapopliteal lesions...
April 1, 2017: Journal of Endovascular Therapy
https://www.readbyqxmd.com/read/28419956/towards-improved-behavioural-testing-in-aquatic-toxicology-acclimation-and-observation-times-are-important-factors-when-designing-behavioural-tests-with-fish
#6
Steven D Melvin, Marie A Petit, Marion C Duvignacq, John P Sumpter
The quality and reproducibility of science has recently come under scrutiny, with criticisms spanning disciplines. In aquatic toxicology, behavioural tests are currently an area of controversy since inconsistent findings have been highlighted and attributed to poor quality science. The problem likely relates to limitations to our understanding of basic behavioural patterns, which can influence our ability to design statistically robust experiments yielding ecologically relevant data. The present study takes a first step towards understanding baseline behaviours in fish, including how basic choices in experimental design might influence behavioural outcomes and interpretations in aquatic toxicology...
April 14, 2017: Chemosphere
https://www.readbyqxmd.com/read/28417585/speckle-variance-optical-coherence-tomography-of-blood-flow-in-the-beating-mouse-embryonic-heart
#7
Olga A Grishina, Shang Wang, Irina V Larina
Efficient separation of blood and cardiac wall in the beating embryonic heart is essential and critical for experiment-based computational modelling and analysis of early-stage cardiac biomechanics. Although speckle variance optical coherence tomography (SV-OCT) relying on calculation of intensity variance over consecutively acquired frames is a powerful approach for segmentation of fluid flow from static tissue, application of this method in the beating embryonic heart remains challenging because moving structures generate SV signal indistinguishable from the blood...
April 18, 2017: Journal of Biophotonics
https://www.readbyqxmd.com/read/28415239/motility-of-escherichia-coli-in-a-quasi-two-dimensional-porous-medium
#8
Juan Eduardo Sosa-Hernández, Moisés Santillán, Jesús Santana-Solano
Bacterial migration through confined spaces is critical for several phenomena, such as biofilm formation, bacterial transport in soils, and bacterial therapy against cancer. In the present work, E. coli (strain K12-MG1655 WT) motility was characterized by recording and analyzing individual bacterium trajectories in a simulated quasi-two-dimensional porous medium. The porous medium was simulated by enclosing, between slide and cover slip, a bacterial-culture sample mixed with uniform 2.98-μm-diameter spherical latex particles...
March 2017: Physical Review. E
https://www.readbyqxmd.com/read/28415233/two-mechanisms-forming-a-comblike-step-pattern-induced-by-a-moving-linear-adatom-source
#9
Masahide Sato, Hitoshi Miura, Makio Uwaha
We carry out phase field simulations to study properties of the comblike step patterns induced by an adatom source. When an adatom source advances right in front of a step, step wandering is caused by the asymmetry of the surface diffusion field and small protrusions are formed. If the velocity of the source V_{p} is smaller than a critical value V_{p}^{c}, the protrusions follow the adatom source with coarsening of the step pattern, and a regular comblike pattern with finger-like protrusions is formed. With a sufficiently small V_{p}, the gap of the supersaturation is large at the adatom source...
March 2017: Physical Review. E
https://www.readbyqxmd.com/read/28415194/migration-of-a-droplet-in-a-cylindrical-tube-in-the-creeping-flow-regime
#10
Binita Nath, Gautam Biswas, Amaresh Dalal, Kirti Chandra Sahu
The migration of a neutrally buoyant droplet in a tube containing another immiscible liquid is investigated numerically in the creeping flow regime. A fully developed velocity profile is imposed at the inlet of the tube. The interface between the two immiscible fluids is captured using a coupled level-set and volume-of-fluid approach. The deformation and breakup dynamics of the droplet are investigated in terms of three dimensionless parameters, namely, the ratio between the radius of the undeformed droplet and the radius of the capillary tube, the viscosity ratio between the dispersed and the continuous phases, and the capillary number that measures the relative importance of the viscous force over the surface tension force...
March 2017: Physical Review. E
https://www.readbyqxmd.com/read/28410946/right-atrial-dysfunction-in-the-fetus-with-severely-regurgitant-tricuspid-valve-disease-a-potential-source-of-cardiovascular-compromise
#11
Lisa W Howley, Nee Scze Khoo, Anita J Moon-Grady, Sonali S Patel, Fayeza Alrais, Wayne Tworetzky, Timothy Colen, Paul Brooks, Jean Trines, Tiina Ojala, Lisa K Hornberger
BACKGROUND: In severe right heart obstruction (RHO), redistribution of cardiac output to the left ventricle (LV) is well tolerated by the fetal circulation. Although the same should be true of severely regurgitant tricuspid valve disease (rTVD) with reduced or no output from the right ventricle, affected fetuses more frequently develop hydrops or suffer intrauterine demise. We hypothesized that right atrium (RA) function is altered in rTVD but not in RHO, which could contribute to differences in outcomes...
April 11, 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/28406944/fixational-saccades-are-more-disconjugate-in-adults-than-in-children
#12
Aasef G Shaikh, Fatema F Ghasia
PURPOSE: Fixational eye movements are of particular interest for three reasons. They are critical for preventing visual fading and enhancing visual perception; their disconjugacy allows scanning in three dimensions, and their neural correlates span through the cortico-striatal, striato-collicular and brainstem networks. Fixational eye movements are altered in various pediatric ophthalmologic and neurologic disorders. The goal of this study was to compare the dynamics of fixational eye movements in normal children and adults...
2017: PloS One
https://www.readbyqxmd.com/read/28405921/the-role-of-early-molecular-response-in-the-management-of-chronic-phase-cml
#13
REVIEW
Patrick Harrington, Aytug Kizilors, Hugues de Lavallade
PURPOSE OF REVIEW: Although tyrosine kinase inhibitors (TKIs) spectacularly improve the disease burden and the overall survival of chronic myeloid leukemia patients, early identification of a subset of poor TKI responders has been recognized as a critical goal to prevent disease progression in these patients. We herein review the past and recent evidence on the impact of early response. RECENT FINDINGS: In the recent years, the achievement of an early molecular response (EMR, defined as 3-month BCR-ABL1 transcript <10% IS) has emerged as a useful tool to identify poor-risk patients...
April 12, 2017: Current Hematologic Malignancy Reports
https://www.readbyqxmd.com/read/28398753/droplet-motion-on-a-shape-gradient-surface
#14
Yanfen Zheng, Jiang Cheng, Cailong Zhou, Haiting Xing, Xiufang Wen, Pihui Pi, Shouping Xu
We demonstrate a facile method to induce water droplet motion on an wedge-shaped superhydrophobic copper surface combining with a poly(dimethylsiloxane) (PDMS) oil layer on it. The unbalanced interfacial tension from the shape gradient offers the actuating force. The superhydrophobicity critically eliminates the droplet contact line pinning and the slippery PDMS oil layer lubricates the droplet motion, which makes the droplet move easily. The maximum velocity and furthest position of droplet motion were recorded and found influenced by the gradient angle...
April 11, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28397001/gait-ataxia-in-humans-vestibular-and-cerebellar-control-of-dynamic-stability
#15
Roman Schniepp, Ken Möhwald, Max Wuehr
During human locomotion, vestibular feedback control is fundamental for maintaining dynamic stability and adapting the gait pattern to external circumstances. Within the supraspinal locomotor network, the cerebellum represents the key site for the integration of vestibular feedback information. The cerebellum is further important for the fine-tuning and coordination of limb movements during walking. The aim of this review article is to highlight the shared structural and functional sensorimotor principles in vestibular and cerebellar locomotion control...
April 10, 2017: Journal of Neurology
https://www.readbyqxmd.com/read/28394902/correlation-of-hippocampal-atrophy-with-hyperhomocysteinemia-in-hemodialysis-patients-an-exploratory-pilot-study
#16
Kyoko Maesato, Takayasu Ohtake, Yasuhiro Mochida, Kunihiro Ishioka, Machiko Oka, Hidekazu Moriya, Sumi Hidaka, Shuzo Kobayashi
BACKGROUND: Cognitive impairment is one of the important critical issues in hemodialysis (HD) patients. However, the associating factors of brain atrophy in HD patients have not been fully elucidated. PURPOSE AND METHODS: Brain magnetic resonance imaging (MRI) was performed in 34 of total 72 HD outpatients in our dialysis center. These MRI images were analyzed by an application software; Voxel-based Specific Regional Analysis System for Alzheimer's Disease (VSRAD)...
2017: PloS One
https://www.readbyqxmd.com/read/28392182/differences-in-cavernosal-artery-parameters-according-to-different-anatomic-sampling-locations-during-the-diagnosis-of-vascular-erectile-dysfunction-using-duplex-ultrasound
#17
Fabio Pezzoni, Fabrizio Ildefonso Scroppo, Giorgio Cavallini
OBJECTIVE: To establish a standard location for examining penile cavernosal arteries (CAs) using dynamic duplex Doppler ultrasound (PDDU) examination in the diagnosis of non-arterial erectile dysfunction (ED) or arterial insufficiency. MATERIALS AND METHODS: Two groups of 105 patients each were enrolled. The first group (age 56.3 ± 6.0 years) displayed clinical patterns of arterial insufficiency; the second group (age 35.2 ± 4.7 years) displayed clinical patterns of non-arterial ED...
April 6, 2017: Urology
https://www.readbyqxmd.com/read/28387692/the-role-of-sensory-augmentation-for-people-with-vestibular-deficits-real-time-balance-aid-and-or-rehabilitation-device
#18
K H Sienko, S L Whitney, W J Carender, C Wall
This narrative review highlights findings from the sensory augmentation field for people with vestibular deficits and addresses the outstanding questions that are critical to the translation of this technology into clinical and/or personal use. Prior research has demonstrated that the real-time use of visual, vibrotactile, auditory, and multimodal sensory augmentation technologies can improve balance during static and dynamic stance tasks within a laboratory setting. However, its application in improving gait requires additional investigation, as does its efficacy as a rehabilitation device for people with vestibular deficits...
2017: Journal of Vestibular Research: Equilibrium & Orientation
https://www.readbyqxmd.com/read/28381985/virtual-normalization-of-physical-impairment-a-pilot-study-to-evaluate-motor-learning-in-presence-of-physical-impairment
#19
Christopher Jarrett, Andrew McDaid
Motor learning is a critical component of the rehabilitation process; however, it can be difficult to separate the fundamental causes of a learning deficit when physical impairment is a confounding factor. In this paper, a new technique is proposed to augment the residual ability of physically impaired patients with a robotic rehabilitation exoskeleton, such that motor learning can be studied independently of physical impairment. The proposed technique augments the velocity of an on-screen cursor relative to the restricted physical motion...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28374762/vortices-and-antivortices-in-two-dimensional-ultracold-fermi-gases
#20
G Bighin, L Salasnich
Vortices are commonly observed in the context of classical hydrodynamics: from whirlpools after stirring the coffee in a cup to a violent atmospheric phenomenon such as a tornado, all classical vortices are characterized by an arbitrary circulation value of the local velocity field. On the other hand the appearance of vortices with quantized circulation represents one of the fundamental signatures of macroscopic quantum phenomena. In two-dimensional superfluids quantized vortices play a key role in determining finite-temperature properties, as the superfluid phase and the normal state are separated by a vortex unbinding transition, the Berezinskii-Kosterlitz-Thouless transition...
April 4, 2017: Scientific Reports
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