keyword
MENU ▼
Read by QxMD icon Read
search

System dynamics

keyword
https://www.readbyqxmd.com/read/28445999/crystal-orientation-effect-on-the-subsurface-deformation-of-monocrystalline-germanium-in-nanometric-cutting
#1
Min Lai, Xiaodong Zhang, Fengzhou Fang
Molecular dynamics simulations of nanometric cutting on monocrystalline germanium are conducted to investigate the subsurface deformation during and after nanometric cutting. The continuous random network model of amorphous germanium is established by molecular dynamics simulation, and its characteristic parameters are extracted to compare with those of the machined deformed layer. The coordination number distribution and radial distribution function (RDF) show that the machined surface presents the similar amorphous state...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28445778/the-impact-of-bilateral-vagotomy-on-the-physostigmine-induced-airway-constriction-in-ferrets
#2
Burim Neziri, Armond Daci, Shaip Krasniqi, Ramadan Sopi, Musa A Haxhiu
Vagal innervations have a great role in the respiratory function and are the main route of signal transmission from respiratory neural centers into the trachea and others conducting airways. We have investigated the role of central mechanisms related to vagal neural pathways and the cholinergic outflow in tracheobronchial smooth muscle tone and lung mechanics parameters. Parameters of lung mechanics such as lung resistance (RL), dynamic compliance (Cdyn) and pressure in bypassed tracheal segment (Ptseg) were measured before and after vagotomy and asphyxia test...
April 23, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28445762/analysis-of-active-transport-by-fluorescence-recovery-after-photobleaching
#3
Maria-Veronica Ciocanel, Jill A Kreiling, James A Gagnon, Kimberly L Mowry, Björn Sandstede
Fluorescence recovery after photobleaching (FRAP) is a well-established experimental technique to study binding and diffusion of molecules in cells. Although a large number of analytical and numerical models have been developed to extract binding and diffusion rates from FRAP recovery curves, active transport of molecules is typically not included in the existing models that are used to estimate these rates. Here we present a validated numerical method for estimating diffusion, binding/unbinding rates, and active transport velocities using FRAP data that captures intracellular dynamics through partial differential equation models...
April 25, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28445754/probing-the-dynamics-of-clot-bound-thrombin-at-venous-shear-rates
#4
Laura M Haynes, Thomas Orfeo, Kenneth G Mann, Stephen J Everse, Kathleen E Brummel-Ziedins
In closed system models of fibrin formation, exosite-mediated thrombin binding to fibrin contributes to clot stability and is resistant to inhibition by antithrombin/heparin while still susceptible to small, active-site inhibitors. Each molecule of fibrin can bind ∼1.6 thrombin molecules at low-affinity binding sites (Kd = 2.8 μM) and ∼0.3 molecules of thrombin at high-affinity binding sites (Kd = 0.15 μM). The goal of this study is to assess the stability of fibrin-bound thrombin under venous flow conditions and to determine both its accessibility and susceptibility to inhibition...
April 25, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28445637/control-of-charge-carriers-trapping-and-relaxation-in-hematite-by-oxygen-vacancy-charge-ab-initio-non-adiabatic-molecular-dynamics
#5
Zhaohui Zhou, Jin Liu, Run Long, Linqiu Li, Liejin Guo, Oleg V Prezhdo
Ultrafast charge recombination in hematite (α-Fe2O3) severely limits its applications in solar energy conversion and utilization, for instance, in photo-electrochemical water splitting. We report the first time-domain ab initio study of charge relaxation dynamics in α-Fe2O3 with and without the oxygen vacancy (Ov) defect, using non-adiabatic molecular dynamics implemented within time-dependent density functional theory. The simulations show that the hole trapping is the rate-limiting step in the electron-hole recombination process for both neutral and ionized Ov systems...
April 26, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28445538/gene-expression-patterns-associated-with-neurological-disease-in-human-hiv-infection
#6
Pietro Paolo Sanna, Vez Repunte-Canonigo, Eliezer Masliah, Celine Lefebvre
The pathogenesis and nosology of HIV-associated neurological disease (HAND) remain incompletely understood. Here, to provide new insight into the molecular events leading to neurocognitive impairments (NCI) in HIV infection, we analyzed pathway dysregulations in gene expression profiles of HIV-infected patients with or without NCI and HIV encephalitis (HIVE) and control subjects. The Gene Set Enrichment Analysis (GSEA) algorithm was used for pathway analyses in conjunction with the Molecular Signatures Database collection of canonical pathways (MSigDb)...
2017: PloS One
https://www.readbyqxmd.com/read/28445419/embedded-spherical-localization-for-micro-underwater-vehicles-based-on-attenuation-of-electro-magnetic-carrier-signals
#7
Daniel-André Duecker, A René Geist, Michael Hengeler, Edwin Kreuzer, Marc-André Pick, Viktor Rausch, Eugen Solowjow
Self-localization is one of the most challenging problems for deploying micro autonomous underwater vehicles ( μ AUV) in confined underwater environments. This paper extends a recently-developed self-localization method that is based on the attenuation of electro-magnetic waves, to the μ AUV domain. We demonstrate a compact, low-cost architecture that is able to perform all signal processing steps present in the original method. The system is passive with one-way signal transmission and scales to possibly large μ AUV fleets...
April 26, 2017: Sensors
https://www.readbyqxmd.com/read/28445417/ins-gnss-integration-for-aerobatic-flight-applications-and-aircraft-motion-surveying
#8
Edgar L V Hinüber, Christian Reimer, Tim Schneider, Michael Stock
This paper presents field tests of challenging flight applications obtained with a new family of lightweight low-power INS/GNSS (inertial navigation system/global satellite navigation system) solutions based on MEMS (micro-electro-mechanical- sensor) machined sensors, being used for UAV (unmanned aerial vehicle) navigation and control as well as for aircraft motion dynamics analysis and trajectory surveying. One key is a 42+ state extended Kalman-filter-based powerful data fusion, which also allows the estimation and correction of parameters that are typically affected by sensor aging, especially when applying MEMS-based inertial sensors, and which is not yet deeply considered in the literature...
April 26, 2017: Sensors
https://www.readbyqxmd.com/read/28445112/tracking-the-evolution-of-non-small-cell-lung-cancer
#9
Mariam Jamal-Hanjani, Gareth A Wilson, Nicholas McGranahan, Nicolai J Birkbak, Thomas B K Watkins, Selvaraju Veeriah, Seema Shafi, Diana H Johnson, Richard Mitter, Rachel Rosenthal, Max Salm, Stuart Horswell, Mickael Escudero, Nik Matthews, Andrew Rowan, Tim Chambers, David A Moore, Samra Turajlic, Hang Xu, Siow-Ming Lee, Martin D Forster, Tanya Ahmad, Crispin T Hiley, Christopher Abbosh, Mary Falzon, Elaine Borg, Teresa Marafioti, David Lawrence, Martin Hayward, Shyam Kolvekar, Nikolaos Panagiotopoulos, Sam M Janes, Ricky Thakrar, Asia Ahmed, Fiona Blackhall, Yvonne Summers, Rajesh Shah, Leena Joseph, Anne M Quinn, Phil A Crosbie, Babu Naidu, Gary Middleton, Gerald Langman, Simon Trotter, Marianne Nicolson, Hardy Remmen, Keith Kerr, Mahendran Chetty, Lesley Gomersall, Dean A Fennell, Apostolos Nakas, Sridhar Rathinam, Girija Anand, Sajid Khan, Peter Russell, Veni Ezhil, Babikir Ismail, Melanie Irvin-Sellers, Vineet Prakash, Jason F Lester, Malgorzata Kornaszewska, Richard Attanoos, Haydn Adams, Helen Davies, Stefan Dentro, Philippe Taniere, Brendan O'Sullivan, Helen L Lowe, John A Hartley, Natasha Iles, Harriet Bell, Yenting Ngai, Jacqui A Shaw, Javier Herrero, Zoltan Szallasi, Roland F Schwarz, Aengus Stewart, Sergio A Quezada, John Le Quesne, Peter Van Loo, Caroline Dive, Allan Hackshaw, Charles Swanton
Background Among patients with non-small-cell lung cancer (NSCLC), data on intratumor heterogeneity and cancer genome evolution have been limited to small retrospective cohorts. We wanted to prospectively investigate intratumor heterogeneity in relation to clinical outcome and to determine the clonal nature of driver events and evolutionary processes in early-stage NSCLC. Methods In this prospective cohort study, we performed multiregion whole-exome sequencing on 100 early-stage NSCLC tumors that had been resected before systemic therapy...
April 26, 2017: New England Journal of Medicine
https://www.readbyqxmd.com/read/28445057/experimental-and-numerical-study-of-the-evaporation-of-water-at-low-pressures
#10
Mohammad Amin Kazemi, David S Nobes, Janet A W Elliott
Although evaporation is considered to be a surface phenomenon, the rate of molecular transport across a liquid-vapor boundary is strongly dependent on the coupled fluid dynamics and heat transfer in the bulk fluids. Recent experimental thermocouple measurements of the temperature field near the interface of evaporating water into its vapor have begun to show the role of heat transfer in evaporation. However, the role of fluid dynamics has not been explored sufficiently. Here, we have developed a mathematical model to describe the coupling of the heat, mass, and momentum transfer in the fluids with the transport phenomena at the interface...
April 26, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28444908/micelles-of-the-chiral-biocompatible-surfactant-1r-2s-dodecyl-2-hydroxy-1-methyl-2-phenylethyl-dimethylammonium-bromide-dmeb-molecular-dynamics-and-fragmentation-patterns-in-gas-phase
#11
David Bongiorno, Serena Indelicato, Leopoldo Ceraulo, Ugo Perricone, Valentina Calabrese, Anna Maria Almerico, Vincenzo Turco Liveri, Marco Tutone
RATIONALE: The study of self-assembly process of surfactant molecules in gas phase is of actually interest for several theoretical and technological reasons related to their possible exploitation as drug carriers, protein shields and cleaning agents in gas phase. METHODS: Stability and fragmentation patterns of singly and multiply charged (either positively or negatively) aggregates of the surfactant (1R,2S)-dodecyl(2-hydroxy-1-methyl-2-phenylethyl) dimethyl ammonium bromide (DMEB) in gas phase have been studied by ion mobility mass spectrometry and tandem mass spectrometry...
April 26, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/28444855/intraguild-interactions-and-behavior-of-spodoptera-frugiperda-and-helicoverpa-spp-on-maize
#12
José P F Bentivenha, Débora G Montezano, Thomas E Hunt, Edson L L Baldin, Julie A Peterson, Vinícius S Victor, Luiz E R Pannuti, Ana M Vélez, Silvana V Paula-Moraes
BACKGROUND: Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is one of the major pests of maize, and is in the same feeding guild of the noctuid pests, Helicoverpa zea (Boddie), and Helicoverpa armigera (Hübner), recently reported in South and North America. The intraguild interactions of these species were assessed in laboratory and field conditions by determining the survival of larvae in interactions scenarios with non-Bt maize silks and ears. Moreover, a video-tracking system was utilized to evaluate behavioral parameters during larval interactions in scenarios with or without food...
April 26, 2017: Pest Management Science
https://www.readbyqxmd.com/read/28444399/development-of-a-multipurpose-scaffold-for-the-display-of-peptide-loops
#13
Maxim Rossmann, Sandra J Greive, Tommaso Moschetti, Michael Dinan, Marko Hyvönen
Protein-protein interactions (PPIs) determine a wide range of biological processes and analysis of these dynamic networks is increasingly becoming a mandatory tool for studying protein function. Using the globular ATPase domain of recombinase RadA as a scaffold, we have developed a peptide display system (RAD display), which allows for the presentation of target peptides, protein domains or full-length proteins and their rapid recombinant production in bacteria. The design of the RAD display system includes differently tagged versions of the scaffold, which allows for flexibility in the protein purification method, and chemical coupling for small molecule labeling or surface immobilization...
April 24, 2017: Protein Engineering, Design & Selection: PEDS
https://www.readbyqxmd.com/read/28443918/ph-responsiveness-of-hydrogels-formed-by-telechelic-polyampholytes
#14
Margarita A Dyakonova, George Gotzamanis, Bart-Jan Niebuur, Natalya S Vishnevetskaya, Konstantinos N Raftopoulos, Zhenyu Di, Sergey K Filippov, Constantinos Tsitsilianis, Christine M Papadakis
We investigate the influence of pH on the rheological and structural properties of hydrogels formed by hydrophobic association of the sticky ends of the triblock terpolymer poly(methyl methacrylate)-b-poly(2-(diethylamino)ethyl methacrylate-co-methacrylic acid)-b-poly(methyl methacrylate) (PMMA-b-P(DEA-co-MAA)-b-PMMA). The middle block is a weak polyampholyte having a pH dependent charge density and sign, which enables tuning of the rheological and structural properties by pH variation. Small-angle neutron scattering (SANS) studies of solutions in D2O at 0...
April 26, 2017: Soft Matter
https://www.readbyqxmd.com/read/28443905/predicting-oligomer-polymer-compatibility-and-the-impact-on-nanoscale-segregation-in-thin-films
#15
Elise F D Sabattié, Jos Tasche, Mark R Wilson, Maximilian W A Skoda, Arwel Hughes, Torsten Lindner, Richard L Thompson
Compatibility between oligomers and polymers was systematically assessed using differential scanning calorimetry (DSC) and was correlated with similarity in saturation and solubility parameter. These measurements enabled validation of detailed volume of mixing calculations using Statistical Association Fluid Theory (SAFT-γ Mie) and molecular dynamics (MD) simulations, which can be used to predict behaviour beyond the experimentally accessible conditions. These simulations confirmed that squalane is somewhat more compatible with poly(isoprene), "PI" than poly(butadiene), "PB", and further enabled prediction of the temperature dependence of compatibility...
April 26, 2017: Soft Matter
https://www.readbyqxmd.com/read/28443836/energy-harvesting-from-aperiodic-low-frequency-motion-using-reverse-electrowetting
#16
Tsung-Hsing Hsu, J A Taylor, T N Krupenkin
Mechanical energy harvesting can provide a promising alternative to electrochemical batteries, which are currently widely utilized to power mobile electronics. In this work we present a theoretical analysis of a recently proposed method of mechanical energy harvesting, which combines a reverse electrowetting phenomenon with the fast self-oscillating process of bubble growth and collapse. We investigate the details of the bubble dynamics and analyze the dependence of the energy generation process on the system parameters...
April 26, 2017: Faraday Discussions
https://www.readbyqxmd.com/read/28443830/paco-sub-2-sub-measurement-in-cerebral-haemodynamics-face-mask-or-nasal-cannulae
#17
Jatinder Singh Minhas, Thompson Robinson, Ronney Panerai
Objective PaCO2 affects cerebral blood flow (CBF) and its regulatory mechanisms, but the effects of CO2 measurement technique on cerebrovascular parameters are unknown. In order to determine if the two most commonly used approaches, face mask (FM) or nasal cannulae (NC), are interchangeable or not, we tested the hypothesis that the use of FM versus NC does not lead to significant differences in CO2-related systemic and cerebrovascular parameters. Approach Recordings of CBF velocity (CBFV), blood pressure (BP), heart rate, and end-tidal CO2 (EtCO2) were performed in 42 subjects during normocapnia (FM or NC) and 5% CO2 inhalation (FM) or hyperventilation (NC)...
April 26, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28443696/the-development-and-modelling-of-devices-and-paradigms-for-transcranial-magnetic-stimulation
#18
Stefan M Goetz, Zhi-De Deng
Magnetic stimulation is a non-invasive neurostimulation technique that can evoke action potentials and modulate neural circuits through induced electric fields. Biophysical models of magnetic stimulation have become a major driver for technological developments and the understanding of the mechanisms of magnetic neurostimulation and neuromodulation. Major technological developments involve stimulation coils with different spatial characteristics and pulse sources to control the pulse waveform. While early technological developments were the result of manual design and invention processes, there is a trend in both stimulation coil and pulse source design to mathematically optimize parameters with the help of computational models...
April 26, 2017: International Review of Psychiatry
https://www.readbyqxmd.com/read/28443654/quantifying-the-self-assembly-behavior-of-anisotropic-nanoparticles-using-liquid-phase-transmission-electron-microscopy
#19
Binbin Luo, John W Smith, Zihao Ou, Qian Chen
For decades, one of the overarching objectives of self-assembly science has been to define the rules necessary to build functional, artificial materials with rich and adaptive phase behavior from the bottom-up. To this end, the computational and experimental efforts of chemists, physicists, materials scientists, and biologists alike have built a body of knowledge that spans both disciplines and length scales. Indeed, today control of self-assembly is extending even to supramolecular and molecular levels, where crystal engineering and design of porous materials are becoming exciting areas of exploration...
April 26, 2017: Accounts of Chemical Research
https://www.readbyqxmd.com/read/28443646/on-the-dynamics-and-control-of-mechanical-properties-of-hierarchical-rotating-rigid-unit-auxetics
#20
Krzysztof K Dudek, Ruben Gatt, Luke Mizzi, Mirosław R Dudek, Daphne Attard, Kenneth E Evans, Joseph N Grima
In this work, we investigate the deformation mechanism of auxetic hierarchical rotating square systems through a dynamics approach. We show how their deformation behaviour, hence their mechanical properties and final configuration for a given applied load, can be manipulated solely by altering the resistance to rotational motion of the hinges within the system. This provides enhanced tunability without necessarily changing the geometry of the system, a phenomenon which is not typically observed in other non-hierarchical unimode auxetic systems...
April 26, 2017: Scientific Reports
keyword
keyword
14070
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"