Search results for "Droplet"
showing 10 items of 127 documents
Lipid droplet-associated proteins in high-fat fed mice with the effects of voluntary running and diet change
2014
Abstract Objective The relation between lipid accumulation and influence of exercise on insulin sensitivity is not straightforward. A proper balance between lipid droplet synthesis, lipolysis, and oxidative metabolism would ensure low local intramyocellular fatty acid levels, thereby possibly protecting against lipotoxicity-associated insulin resistance. This study investigated whether the accumulation of triglycerides and lipid droplets in response to high availability of fatty acids after high-fat feeding would parallel the abundance of intramyocellular perilipin proteins, especially PLIN5. The effects on these variables after diet change or voluntary running exercise intervention in skel…
Heterogeneous nucleation of a droplet pinned at a chemically inhomogeneous substrate: A simulation study of the two-dimensional Ising case
2018
Heterogeneous nucleation is studied by Monte Carlo simulations and phenomenological theory, using the two-dimensional lattice gas model with suitable boundary fields. A chemical inhomogeneity of length b at one boundary favors the liquid phase, while elsewhere the vapor is favored. Switching on the bulk field Hb favoring the liquid, nucleation and growth of the liquid phase starting from the region of the chemical inhomogeneity are analyzed. Three regimes occur: for small fields, Hb bcrit, the critical droplet radius is so large that a critical droplet having the contact angle θc required by Young's equation in the region of the chemical inhomogeneity does not yet "fit" there since the base…
Imbibition of Femtoliter-Scale DNA-Rich Aqueous Droplets into Porous Nylon Substrates by Molecular Printing
2019
This work presents the first reported imbibition mechanism of femtoliter (fL)-scale droplets produced by microchannel cantilever spotting (μCS) of DNA molecular inks into porous substrates (hydrophilic nylon). Differently from macroscopic or picoliter droplets, the downscaling to the fL-size leads to an imbibition process controlled by the subtle interplay of evaporation, spreading, viscosity, and capillarity, with gravitational forces being quasi-negligible. In particular, the minimization of droplet evaporation, surface tension, and viscosity allows for a reproducible droplet imbibition process. The dwell time on the nylon surface permits further tuning of the droplet lateral size, in acc…
Oil-in-Water fL Droplets by Interfacial Spontaneous Fragmentation and Their Electrical Characterization
2019
Inkjet printing is here employed for the first time as a method to produce femtoliter-scale oil droplets dispersed in water. In particular, picoliter-scale fluorinated oil (FC40) droplets are printed in the presence of perfluoro-1-octanol surfactant at a velocity higher than 5 m/s. Femtoliter-scale oil droplets in water are spontaneously formed through a fragmentation process at the water/air interface using minute amounts of nonionic surfactant (down to 0.003% v/v of Tween 80). This fragmentation occurs by a Plateau-Rayleigh mechanism at a moderately high Weber number (10(1)). A microfluidic chip with integrated microelectrodes allows droplets characterization in terms of number and diamet…
HPMA-based block copolymers promote differential drug delivery kinetics for hydrophobic and amphiphilic molecules.
2015
Abstract We describe a method how polymeric nanoparticles stabilized with (2-hydroxypropyl)methacrylamide (HPMA)-based block copolymers are used as drug delivery systems for a fast release of hydrophobic and a controlled release of an amphiphilic molecule. The versatile method of the miniemulsion solvent-evaporation technique was used to prepare polystyrene (PS) as well as poly-d/l-lactide (PDLLA) nanoparticles. Covalently bound or physically adsorbed fluorescent dyes labeled the particles’ core and their block copolymer corona. Confocal laser scanning microscopy (CLSM) in combination with flow cytometry measurements were applied to demonstrate the burst release of a fluorescent hydrophobic…
Chemical characterization of gallium droplets grown by LP-MOCVD.
2006
International audience; This study is concerned with the chemical characterization of metallic gallium droplets, obtained on silicon (1 0 0) substrates with a single growth step, by the LP-MOCVD technique with TMGa like precursor. These structures are characterized by SIMS, XPS and TEM. The analyses results lead to a structure proposition for the droplets. The core is composed of metastable metallic gallium with a non-negligible carbon quantity probably coming from incomplete precursor decomposition. The outer part, composed of gallium oxide maintains the structure stability. Covering of the substrate by a thin gallium layer of gallium compounds is observed.
Growth of low-density vertical quantum dot molecules with control in energy emission
2010
This article is distributed under the terms of the Creative Commons Attribution Noncommercial License.-- This article is part of the series 8th International Workshop on Epitaxial Semiconductors on Patterned Substrates and Novel Index Surfaces.
The Detection of Androgen Receptor Splice Variant 7 in Plasma-derived Exosomal RNA Strongly Predicts Resistance to Hormonal Therapy in Metastatic Pro…
2017
Abstract Background The androgen receptor splice variant 7 (AR-V7) is associated with resistance to hormonal therapy in castration-resistant prostate cancer (CRPC). Due to limitations of the methods available for AR-V7 analysis, the identification of a reliable detection method may facilitate the use of this biomarker in clinical practice. Objective To confirm AR-V7 as a predictor of resistance to hormonal therapy and develop a new approach to assess AR-V7 by highly sensitive digital droplet polymerase chain reaction (ddPCR) in plasma-derived exosomal RNA. Design, setting, and participants Plasma samples were collected from 36 CRPC patients before they began second-line hormonal treatment. …
Spreading dynamics of three-dimensional droplets by the lattice-Boltzmann method
2000
Abstract We have simulated spreading of small droplets on smooth and rough solid surfaces using the three-dimensional lattice-Boltzmann method. We present results for the influence of the initial distance and shape of the drop from the surface on scaling of droplet radius R as a function of time. For relatively flat initial drop shapes our observations are consistent with Tanner's law R ∼ t q , where q =1/10. For increasingly spherical initial shapes, the exponent q increases rapidly being above one half for spherical droplets initially just above the surface. As expected, surface roughness slows down spreading, decreases the final drop radius, and results in irregular droplet shape due to …
Lipid rafts: a signalling platform linking lipoprotein metabolism to atherogenesis.
2012
Lipid rafts are microdomains of the plasma membrane which are enriched in cholesterol and sphingolipids. They serve as a platform for signal transduction, in particular during immune and inflammatory responses. As hypercholesterolemia and inflammation are two key elements of atherogenesis, it is conceivable that the cholesterol and cholesterol oxide content of lipid rafts might influence the inflammatory signalling pathways, thus modulating the development of atherosclerosis. In support of this emerging view, lipid rafts have been shown to be involved in several key steps of atherogenesis, such as the oxysterol-mediated apoptosis of vascular cells, the blunted ability of high density lipopr…