PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 12962401

Polarized light reflection from strained sinusoidal surfaces.

Brian Schulkin·Hee C Lim·Nejat Guzelsu·Glen Jannuzzi·John F Federici
View original source ↗Export metadata ↓

Abstract

We propose optical polarization imaging as a minimally invasive technique for measuring the mechanical properties of plastics and soft tissues through their change in reflectance properties with applied strain or force. We suggest that changes in surface roughness are responsible for the linear reflectivity changes with applied stretch or strain. Several aspects of this model are tested, including the dependence on the angle of incidence, the change in scattering and absorption coefficients with strain, and the lateral spatial resolution. The application of the technique to multilayer structures such as skin and competing optical effects such as laser speckle are discussed.

Explore related subjects

AbsorptionHumansLasersMicroscopy, PolarizationModels, TheoreticalScattering, RadiationSkinSkin Physiological PhenomenaStress, MechanicalJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Brian Schulkin, Hee C Lim, Nejat Guzelsu, Glen Jannuzzi, John F Federici. 2003-09-01. Polarized light reflection from strained sinusoidal surfaces.. https://doi.org/10.1364/ao.42.005198

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2004

Preparation of a biodegradable matrix through polyion complex formation by mixing polylactide-based microspheres having oppositely charged surfaces.

The aggregation of polyions into microsphere (MS) complexes was studied as a preparative method for the construction of a biodegradable matrix. Aqueous suspensions of polylactide (PLA)-based MSs with positively and negatively charged surfaces, MS(K(3)(4+)-PLA) and MS(E(3)(4-)-PLA), respectively, immediately formed aggregates when mixed. The effects of the stoichiometry of the charged groups on the surfaces of the MSs and the ionic strength of the medium on aggregate formation, as well as the degradation behavior of the polyion complex (PIC) matrix over time, were investigated.

Absorption↗
PubMed2004

Needle concentrator for gas chromatographic determination of BTEX in aqueous samples.

A simple method of solventless extraction of volatile organic compounds (BTEX) from aqueous samples was developed and validated. A new arrangement of the full volume inside needle capillary adsorption trap (INCAT) device with Porapak Q as a sorbent material and wet alumina as a source of desorptive water vapour flow in a closed analytical system is presented. The analytical characteristics of developed device and of compared purge-and-trap (PTI) device for BTEX compounds are similar; the limits of detection as well as quantification are lower than 1 microg l(-1).

Absorption↗
PubMed2004

A microdialysis model to examine nasal drug delivery and olfactory absorption in rats using lidocaine hydrochloride as a model drug.

Targeting of the central nervous system by direct drug transport from the nose to the brain has gained increased attention through the last decade. In the present study, a model for olfactory drug absorption has been investigated using intravenous and unilateral nasal administration of lidocaine hydrochloride in rats. To investigate the possible drug delivery aspects of this route of transport to a central part of the brain a microdialysis model using in vivo recovery by calibrator was applied to the systemic blood and to right and left striatum. The integrity of the blood-brain barrier was evaluated following microdialysis probe implantation. The in vivo experiments were carried out as a cross-over study in rats. The drainage from the nasal cavity was not restricted by occlusion. It was found that true unbound lidocaine concentrations could be calculated from in vivo recovery measurements of retrodialysis of prilocaine hydrochloride. The relative in vivo recoveries in striatum (11.3%) and blood (24.0%) were significantly lower than in vitro (31.3 and 44.9%). The blood-brain barrier was found to retain its physical integrity when evaluated one hour after probe implantation. From pharmacokinetic modelling of the time-concentration curves it was found that the absorption rates and area under the curve (AUC) values of lidocaine in left and right striatum were not statistically different following nasal and intravenous administration, respectively. The average nasal bioavailabilities of lidocaine in blood, left and right striatum were 85, 103 and 129%, respectively. It was concluded that no significant olfactory absorption to striatum was evident in the present study. However, the method should be applicable to studies of drug delivery to blood and brain following nasal administration of other drugs.

Absorption↗