keyword
MENU ▼
Read by QxMD icon Read
search

particle tracking

keyword
https://www.readbyqxmd.com/read/29791804/environmentally-relevant-freeze-thaw-cycles-enhance-the-redox-mediated-morphological-changes-of-silver-nanoparticles
#1
Xiaoru Guo, Yongguang Yin, Zhiqiang Tan, Jing-Fu Liu
Silver nanoparticles (AgNPs) are inevitably released into natural systems, particularly into aquatic environments, where they are oxidized and release Ag+ , which is reduced back to AgNPs. Environmental freeze-thaw cycles or freezing may accelerate the dynamic transformation between AgNPs and Ag+ . Herein, the significant morphological changes caused by freezing treatments were assessed by UV-vis spectroscopy and high-resolution transmission electron microscopy, which revealed that reductive regeneration, particle fusion, and coalescence of the AgNPs occurred...
May 23, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29791262/flow-recirculation-in-cartilaginous-ring-cavities-of-human-trachea-model
#2
Jose Montoya Segnini, Humberto Bocanegra Evans, Luciano Castillo
BACKGROUND: Despite the prevailing assumption of "smooth trachea walls" in respiratory fluid dynamics research, recent investigations have demonstrated that cartilaginous rings in the trachea and main bronchi have a significant effect on the flow behavior and in particle deposition. However, there is not enough detailed information about the underlying physics of the interaction between the cartilage rings and the flow. MATERIALS AND METHODS: This study presents an experimental observation of a simplified Weibel-based model of the human trachea and bronchi with cartilaginous rings...
May 23, 2018: Journal of Aerosol Medicine and Pulmonary Drug Delivery
https://www.readbyqxmd.com/read/29790493/quantum-dot-conjugated-nanobodies-for-multiplex-imaging-of-protein-dynamics-at-synapses
#3
Souvik Modi, Nathalie F Higgs, David Sheehan, Lewis D Griffin, Josef T Kittler
Neurons communicate with each other through synapses, which show enrichment for specialized receptors. Although many studies have explored spatial enrichment and diffusion of these receptors in dissociated neurons using single particle tracking, much less is known about their dynamic properties at synapses in complex tissue like brain slices. Here we report the use of smaller and highly specific quantum dots conjugated with a recombinant single domain antibody fragment (VHH fragment) against green fluorescent protein to provide information on diffusion of adhesion molecules at the growth cone and neurotransmitter receptors at synapses...
May 23, 2018: Nanoscale
https://www.readbyqxmd.com/read/29789440/objective-evaluation-of-ram-and-buck-sperm-motility-by-using-novel-sperm-tracker-software
#4
Francisco Buchelly Imbachí, Lucia Zalazar, Juan Ignacio Pastore, Micaela Belén Greco, Maria Iniesta Cuerda, Jose Julian Garde, A J Soler, Virginia Ballarin, Andreina Cesari
This work offers researchers the first version of an open-source sperm tracker software (Sperm Motility Tracker V1.0) containing a novel suit of algorithms to analyze sperm motility using ram and buck sperm as models. The computer-assisted semen analysis (CASA) is used in several publications with increasing trend worldwide in the last years, showing the importance of objective methodologies to evaluate semen quality. However, commercial systems are costly and versatility is constrained. In the proposed method, segmentation is applied and the tracking stage is performed by using individual Kalman filters and a simplified occlusion handling method...
May 22, 2018: Reproduction: the Official Journal of the Society for the Study of Fertility
https://www.readbyqxmd.com/read/29789404/new-approaches-for-assessing-squid-fin-motions-coupling-proper-orthogonal-decomposition-with-volumetric-particle-tracking-velocimetry
#5
Ian K Bartol, Paul S Krueger, Carly A York, Joseph T Thompson
Squids, which swim using a coupled fin/jet system powered by muscular hydrostats, pose unique challenges for the study of locomotion. The high flexibility of the fins and complex flow fields generated by distinct propulsion systems require innovative techniques for locomotive assessment. For this study, we used proper orthogonal decomposition (POD) to decouple components of the fin motions and defocusing digital particle tracking velocimetry (DDPTV) to quantify the resultant 3D flow fields. Kinematic footage and DDPTV data were collected from brief squid Lolliguncula brevis [3...
May 22, 2018: Journal of Experimental Biology
https://www.readbyqxmd.com/read/29787689/patient-specific-multiscale-computational-fluid-dynamics-assessment-of-embolization-rates-in-the-hybrid-norwood-effects-of-size-and-placement-of-the-reverse-blalock-taussig-shunt
#6
Ray Otto Prather, John Seligson, Marcus Ni, Eduardo Divo, Alain Kassab, William DeCampli
The hybrid Norwood operation is performed to treat hypoplastic left heart syndrome. Distal arch obstruction may compromise flow to the brain. In a variant of this procedure, a synthetic graft (RBTS) is placed between the pulmonary trunk and innominate artery to improve upper torso blood flow. Thrombi originating in the graft may embolize to the brain. In this study we used computational fluid dynamics (CFD) and particle tracking to investigate the patterns of particle embolization as a function of the anatomic position of the RBTS...
May 22, 2018: Canadian Journal of Physiology and Pharmacology
https://www.readbyqxmd.com/read/29787674/single-quantum-dot-tracking-reveals-serotonin-transporter-diffusion-dynamics-are-correlated-with-cholesterol-sensitive-threonine-276-phosphorylation-status-in-primary-midbrain-neurons
#7
Danielle M Bailey, Mackenzie A Catron, Oleg Kovtun, Robert L Macdonald, Qi Zhang, Sandra J Rosenthal
Serotonin transporter (SERT) terminates serotonin signaling in the brain by enabling rapid clearance of the neurotransmitter. SERT dysfunction has been associated with a variety of psychiatric disorders, including depression, anxiety, and autism. Visualizing SERT behavior at the single molecule level in endogenous systems remains a challenge. In this study, we utilize quantum dot (QD) single particle tracking (SPT) to capture SERT dynamics in primary rat midbrain neurons. Membrane microenvironment, specifically membrane cholesterol, plays a key role in SERT regulation and has been found to affect SERT conformational state...
May 24, 2018: ACS Chemical Neuroscience
https://www.readbyqxmd.com/read/29786426/influence-of-enzyme-quantity-and-distribution-on-the-self-propulsion-of-non-janus-urease-powered-micromotors
#8
Tania Patiño, Natalia Feiner-Gracia, Xavier Arque, Albert Miguel-López, Anita Jannasch, Tom Stumpp, Erik Schäffer, Lorenzo Albertazzi, Samuel Sanchez
The use of enzyme catalysis to power micro and nanomachines offers unique features such as biocompatibility, versatili-ty and fuel bioavailability. Yet, the key parameters underlying the motion behavior of enzyme-powered motors are not completely understood. Here, we investigate the role of enzyme distribution and quantity on the generation of active mo-tion. Two different micromotor architectures based on either polystyrene (PS) or polystyrene coated with a rough silicon dioxide shell (PS@SiO2) were explored...
May 22, 2018: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/29780799/mixing-time-inversion-and-multiple-emulsion-formation-in-a-limonene-and-water-pickering-emulsion
#9
Laura Sawiak, Katherine Bailes, David Harbottle, Paul S Clegg
It has previously been demonstrated that particle-stabilized emulsions comprised of limonene, water and fumed silica particles exhibit complex emulsification behavior as a function of composition and the duration of the emulsification step. Most notably the system can invert from being oil-continuous to being water-continuous under prolonged mixing. Here we investigate this phenomenon experimentally for the regime where water is the majority liquid. We prepare samples using a range of different emulsification times and we examine the final properties in bulk and via confocal microscopy...
2018: Frontiers in Chemistry
https://www.readbyqxmd.com/read/29780184/pore-scale-hydrodynamics-in-a-progressively-bioclogged-three-dimensional-porous-medium-3-d-particle-tracking-experiments-and-stochastic-transport-modeling
#10
M Carrel, V L Morales, M Dentz, N Derlon, E Morgenroth, M Holzner
Biofilms are ubiquitous bacterial communities that grow in various porous media including soils, trickling, and sand filters. In these environments, they play a central role in services ranging from degradation of pollutants to water purification. Biofilms dynamically change the pore structure of the medium through selective clogging of pores, a process known as bioclogging. This affects how solutes are transported and spread through the porous matrix, but the temporal changes to transport behavior during bioclogging are not well understood...
March 2018: Water Resources Research
https://www.readbyqxmd.com/read/29776020/paramagnetic-colloids-chaotic-routes-to-clusters-and-molecules
#11
Hamed Abdi, Rasam Soheilian, Randall M Erb, Craig E Maloney
We present computer simulations and experiments on dilute suspensions of superparamagnetic particles subject to rotating magnetic fields. We focus on chains of four particles and their decay routes to stable structures. At low rates, the chains track the external field. At intermediate rates, the chains break up but perform a periodic (albeit complex) motion. At sufficiently high rates, the chains generally undergo chaotic motion at short times and decay to either closely packed clusters or more dispersed, colloidal molecules at long times...
March 2018: Physical Review. E
https://www.readbyqxmd.com/read/29770603/t-cell-tracking-using-cerenkov-and-radioluminescence-imaging
#12
F Boschi, F De Sanctis, S Ugel, A E Spinelli
Cancer immunotherapy is a promising strategy based on the ability of the immune system to kill selected cells. In the development of an effective T-cell therapy the non-invasive cell tracking methods play a crucial role. Here we investigate the potentialities of T-cell marked with radionuclides in order to detect their localization with imaging techniques in small animal rodents. A protocol to label T-cells with 32 P-ATP was tested and evaluated. The homing of 32 P-ATP labeled T lymphocytes was investigated by Cerenkov luminescence imaging and radioluminescence imaging The first approach relies on the acquisition of Cerenkov photons produced by the beta particles emitted by the 32 P internalized by lymphocytes; the second one on the detection of photons coming from the conversion of radioactive energy in light done by scintillator crystals layered on the animals...
May 16, 2018: Journal of Biophotonics
https://www.readbyqxmd.com/read/29762018/combining-measurements-from-mobile-monitoring-and-a-reference-site-to-develop-models-of-ambient-ultrafine-particle-number-concentration-at-residences
#13
Matthew C Simon, Allison P Patton, Elena N Naumova, Jonathan I Levy, Prashant Kumar, Doug Brugge, John L Durant
Significant spatial and temporal variation in ultrafine particle (UFP; <100 nanometers in diameter) concentrations creates challenges in developing predictive models for epidemiological investigations. We compared the performance of land-use regression models built by combining mobile and stationary measurements (hybrid model) with a regression model built using mobile measurements only (mobile model) in Chelsea and Boston, MA (USA). In each study area, particle number concentration (PNC; a proxy for UFP) was measured at a stationary reference site and with a mobile laboratory driven along a fixed route during a ~1-year monitoring period...
May 15, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/29762015/preferential-pt-nanocluster-seeding-at-grain-boundary-dislocations-in-polycrystalline-monolayer-mos-2
#14
Shanshan Wang, Hidetaka Sawada, Xiaoyu Han, Si Zhou, Sha Li, Zheng Xiao Guo, Angus I Kirkland, Jamie H Warner
We show that Pt nanoclusters preferentially nucleate along the grain boundaries (GBs) in polycrystalline MoS2 monolayer films, with dislocations acting as the seed site. Atomic resolution studies by aberration-corrected annular dark-field scanning transmission electron microscopy reveal periodic spacing of Pt nanoclusters with dependence on GB tilt angles and random spacings for the antiphase boundaries ( i.e., 60°). Individual Pt atoms are imaged within the dislocation core sections of the GB region, with various positions observed, including both the substitutional sites of Mo and the hollow center of the octahedral ring...
May 15, 2018: ACS Nano
https://www.readbyqxmd.com/read/29758423/tracking-enteric-viruses-in-green-vegetables-from-central-argentina-potential-association-with-viral-contamination-of-irrigation-waters
#15
V E Prez, L C Martínez, M Victoria, M O Giordano, G Masachessi, V E Ré, J V Pavan, R Colina, P A Barril, S V Nates
Consumption of green vegetable products is commonly viewed as a potential risk factor for infection with enteric viruses. The link between vegetable crops and fecally contaminated irrigation water establishes an environmental scenario that can result in a risk to human health. The aim of this work was to analyze the enteric viral quality in leafy green vegetables from Córdoba (Argentina) and its potential association with viral contamination of irrigation waters. During July-December 2012, vegetables were collected from peri-urban green farms (n = 19) and its corresponding urban river irrigation waters (n = 12)...
May 11, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29757420/measurements-of-spatial-correlations-of-ionisation-clusters-in-the-track-of-carbon-ions-first-results
#16
Marcin Pietrzak, Stanislaw Pszona, Aliaksandr Bantsar
An attempt towards an experimental set up which could provide the experimental data on correlation processes occurred simultaneously in two distanced DNA targets within a charged particle track is presented. A modified Jet Counter nanodosemeter was used in two experiments with carbon ions with mean energies of 52 and 23 MeV. The probability distributions of the correlated pairs of ionisation clusters produced in two neighbouring sensitive volumes are presented. A question of potential new descriptors of radiation quality is raised...
May 11, 2018: Radiation Protection Dosimetry
https://www.readbyqxmd.com/read/29757291/virus-delivery-of-crispr-guides-to-the-murine-prostate-for-gene-alteration
#17
Maria Riedel, Martin F Berthelsen, Latifa Bakiri, Erwin F Wagner, Martin K Thomsen
With an increasing incidence of prostate cancer, identification of new tumor drivers or modulators is crucial. Genetically engineered mouse models (GEMM) for prostate cancer are hampered by tumor heterogeneity and its complex microevolution dynamics. Traditional prostate cancer mouse models include, amongst others, germline and conditional knockouts, transgenic expression of oncogenes, and xenograft models. Generation of de novo mutations in these models is complex, time-consuming, and costly. In addition, most of traditional models target the majority of the prostate epithelium, whereas human prostate cancer is well known to evolve as an isolated event in only a small subset of cells...
April 27, 2018: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29756830/inertial-movements-of-the-iris-as-the-origin-of-postsaccadic-oscillations
#18
S Bouzat, M L Freije, A L Frapiccini, G Gasaneo
Recent studies on the human eye indicate that the pupil moves inside the eyeball due to deformations of the iris. Here we show that this phenomenon can be originated by inertial forces undergone by the iris during the rotation of the eyeball. Moreover, these forces affect the iris in such a way that the pupil behaves effectively as a massive particle. To show this, we develop a model based on the Newton equation on the noninertial reference frame of the eyeball. The model allows us to reproduce and interpret several important findings of recent eye-tracking experiments on saccadic movements...
April 27, 2018: Physical Review Letters
https://www.readbyqxmd.com/read/29754007/magnetic-particle-imaging-for-radiation-free-sensitive-and-high-contrast-vascular-imaging-and-cell-tracking
#19
REVIEW
Xinyi Y Zhou, Zhi Wei Tay, Prashant Chandrasekharan, Elaine Y Yu, Daniel W Hensley, Ryan Orendorff, Kenneth E Jeffris, David Mai, Bo Zheng, Patrick W Goodwill, Steven M Conolly
Magnetic particle imaging (MPI) is an emerging ionizing radiation-free biomedical tracer imaging technique that directly images the intense magnetization of superparamagnetic iron oxide nanoparticles (SPIOs). MPI offers ideal image contrast because MPI shows zero signal from background tissues. Moreover, there is zero attenuation of the signal with depth in tissue, allowing for imaging deep inside the body quantitatively at any location. Recent work has demonstrated the potential of MPI for robust, sensitive vascular imaging and cell tracking with high contrast and dose-limited sensitivity comparable to nuclear medicine...
May 10, 2018: Current Opinion in Chemical Biology
https://www.readbyqxmd.com/read/29753778/understanding-protein-mobility-in-bacteria-by-tracking-single-molecules
#20
REVIEW
Achillefs N Kapanidis, Stephan Uphoff, Mathew Stracy
Protein diffusion is crucial for understanding the formation of protein complexes in vivo, and has been the subject of many fluorescence microscopy studies in cells; however, such microscopy efforts are often limited by low sensitivity and resolution. During the past decade, these limitations have been addressed by new super-resolution imaging methods, most of which rely on single-particle tracking and single-molecule detection; these methods are revolutionizing our understanding of molecular diffusion inside bacterial cells by directly visualizing the motion of proteins and the effects of the local and global environment on diffusion...
May 10, 2018: Journal of Molecular Biology
keyword
keyword
84914
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"