Development of an optical fiber fluorescence setup for in-situ PAHs detection in porous media. Application to pyranine transport in sand columns

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The most accurate way of measuring water discharge in a mountain stream is to use a concrete structure (like a Parshall flume or a weir), so that the bed elevation is known and hyporheic flow is substantially reduced. This technique is costly, provides only a one-point measurement and it may be overtopped or damaged during floods. An alternative is offered by non-intrusive monitoring techniques, which do not come into contact with the flow.Non-intrusive monitoring techniques do not measure a river's dischar

Using (2712.4 +/- 14.3) x 10(6) psi(3686) events collected by the BESIII detector operating at the BEPCII collider, we present the first observations of the decays chi(cJ) (J = 0, 1, 2) -> p (p) over bar eta pi(0). Their decay branching fractions are determined to be B(chi(c0) -> p (p) over bar eta pi(0)) = (2.42 +/- 0.07 +/- 0.19) x 10(-4), B(chi(c1) -> p (p) over bar eta pi(0)) = (1.95 +/- 0.05 +/- 0.12) x 10(-4), and B(chi(c2) -> p (p) over bar eta pi(0)) = (1.33 +/- 0.05 +/- 0.08) x 10(-4), where the fi

This semester project deals with the study of at fully clamped plates with various geome- tries (circular and square), piezoelectric properties and uniformly distributed load (normal to the surface). The stress distribution is analyzed in order to obtain an electrical displacement. The objective is to distinguish positive and negative stresses areas in our plate in order to dene an area for current measurements for microphone applications. For the circular plate, a straightforward analytical resolution of t

An optimization based algorithm is proposed for solving elliptic problems with highly oscillatory coecients that do not exhibit scale separation in a subregion of the physical domain. The given method, written as a constrained minimization problem couples a numerical homogenization method in the subregion of the physical domain with scale separation with a ne scale solver in subregions without scale separation. The unknown boundary conditions of both problems in the overlap region are determined by minimizi

We present a new method for lysis of single cells in continuous flow, where cells are sequentially trapped, lysed and released in an automatic process. Using optimized frequencies, dielectrophoretic trapping allows exposing cells in a reproducible way to high electrical fields for long durations, thereby giving good control on the lysis parameters. In situ evaluation of cytosol extraction on single cells has been studied for Chinese hamster ovary (CHO) cells through out-diffusion of fluorescent molecules fo

Hybrid choice models have proved to be a powerful framework that integrates attitudinal and perceptional data into discrete choice models. However the measurement component of such a framework often fails to exploit individual-specific information that might affect the way subjects answer to indicators of opinion. In this paper we propose an HCM with a measurement model that takes into account heterogeneity in the response behavior. Precisely, we capture effects of exaggeration in answers to psychometrics.

The measurement of tissue and cell oxygenation is important for understanding cell metabolism. We have addressed this problem with a novel optical technique, called triplet imaging, that exploits oxygen-induced triplet lifetime changes and is compatible with a variety of fluorophores. A modulated excitation of varying pulse widths allows the extraction of the lifetime of the essentially dark triplet state using a high-fluorescence signal intensity. This enables the monitoring of fast kinetics of oxygen conc

This paper presents Digital Holographic Microscopy (DHM) quantitative measurements of transparent high aspect-ratio microstructures. Our experiment was performed using a digital holographic microscope in transmission configuration with a 60x magnification 1.3 NA oil immersion microscope objective, with a diode laser source at 664 nm. We used a calculation model based on the use of two immersion liquids for the experiment, the first one to resolve the phase jumps by using a refractive index liquid close to t

The advent of scanning near-field optical microscopy (SNOM) has augmented at a microscopic level the usefulness of optical spectroscopy in the region between 300 nm and 10 mum. Two-dimensional imaging of chemical constituents makes this a very attractive and powerful new approach. In this paper we show SNOM results obtained in several geometrical configurations on boron clusters in silicon, Li clusters embedded in a LiF sample and BN growth on silicon. We also show some results on the wavelength dependence

Catalytic processes and in particular heterogeneous catalysis are vital for todays industry. However, many industrial catalytic processes require high temperatures and pressures to work efficiently. This stands in contrast to biological catalysts, which function under ambient temperatures and atmospheric pressures and excel in catalytic activity and selectivity. We may learn something from nature by studying the size-dependent reactivity of small metal particles resembling the active centers of biological c

The physical activity in normal daily life is determined to a large extent by the functional ability of a subject. As a result, the measurement of the physical activity that a subject performs spontaneously could be a useful and objective measurement of disability, particularly in patients with disease-related functional impairment. The aim of this study is to provide an accurate method for the measurement and analysis of the physical activity under normal life conditions. Using three kinematical sensors st

This paper discusses the self-assembly of block copolymers into vesicular morphology. After a brief state of art of the field, a system based on an amphiphilic poly(butadiene)- b-poly(-L-glutamic acid) (PB- b-PGA) diblock copolymer in aqueous solution is discussed in detail. The aggregation behavior of this block copolymer has been investigated by means of fluorescence spectroscopy, dynamic (DLS) and static (SLS) light scattering as well as transmission electron microscopy (TEM). The diblock copolymer was f

The present invention provides novel methods for detecting the incorporation of a nucleotide after a single base extension reaction. The methods make use of the Fluorescence Resonance Energy Transfer (FRET) effect generated by two fluorophores linked to the same nucleic acid strand. The methods can be used, either in solution or a solid support, for applications requiring the rapid and precise identification of a nucleotide in a specific position of a nucleic acid, as for genotyping studies

An instrumentation is being developed to draw a fluorescence life-time map of tissue endoscopically. This fluorescence life-time of an endogenous or exogenous fluorochrome gives information about the physico-chemical environment which is thought to vary between normal and diseased tissue. The excitation light from a cw laser is modulated in amplitude at high frequencies by an electro-optic modulator and delivered to the endoscopic site through an optical fiber. The image of the tissue is spectrally split in

Fano line shapes are reported in the excitation spectrum of the total fluorescence of NO trapped in Kr matrixes. They result from the homogeneous configuration mixing of the sharp valence vibrational bands B2P(v'=12,15,18)-X2P(v''=0) with the broadened multiphonon Rydberg vibrational bands C2P(v'=0,1,2)-X2P(v''=0). The main features of the spectrum are reproduced by a simulation. [on SciFinder (R)]

Collective Thomson scattering, using a high-power pulsed D2O laser at 385-mu-m and a heterodyne receiver system, has provided local ion temperature (T(i)) measurements of the plasma in the tokamak chauffage Alfven (TCA) tokamak. Recent improvements in the noise-equivalent power of the Schottky barrier diode mixers permitted us to achieve a typical precision of +/- 12% for a single shot measurement at densities above 10(20) m-3. Even at densities of standard TCA discharges (5 x 10(19) m-3) the uncertainty is

Contact potential difference (CPD) measurements using a Kelvin probe coupled with synchrotron radiation are used to investigate various aspects of the problem of surface photovoltage (SPV) induced by the synchrotron radiation at (110) and (100) GaAs surfaces. A large and quasipermanent SPV is found at surfaces of low doped and low temperature (110) samples. SPV discharge mechanisms are investigated. Finally, the CPD technique is used to define conditions which minimize SPV and allow accurate measurements of

Development of an optical fiber fluorescence setup for in-situ PAHs detection in porous media. Application to pyranine transport in sand columns

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Relating free-surface flow and discharge in mountain streams

Measurement of the Branching Fraction for the Decay Χcj → p(p)over-barηπ0

Performance of Piezoelectric MEMS Microphones

An optimization-based multiscale coupling method

In situ evaluation of single-cell lysis by cytosol extraction observation through fluorescence decay and dielectrophoretic trapping time

Accounting for response behavior heterogeneity in the measurement of attitudes: an application to demand for electric vehicles

Triplet imaging of oxygen consumption during the contraction of a single smooth muscle cell (A7r5)

Measurements of corner cubes microstructures by high-magnification digital holographic microscopy

Optical nanospectroscopy applications in material science

Design of a variable-temperature scanning tunneling microscope to study reaction intermediates in heterogeneous catalysis

Ambulatory system for the quantitative and qualitative analysis of gait and posture in chronic pain patients treated with spinal cord stimulation

From supramolecular polymersomes to stimuli-responsive nano-capsules based on poly(diene-b-peptide) diblock copolymers

Nucleotide detection by fluorescence resonance energy transfer and methods thereof

Endoscopic tissue fluorescence life-time imaging by frequency domain light-induced fluorescence

Fano profiles on multiphonon continua in electronic transitions of matrix-isolated nitric oxide

Ion Temperature-Measurements in a Tokamak by Collective Thomson Scattering

Surface Photovoltage and Band Bending at Metal Gaas Interfaces - a Contact Potential Difference and Photoemission Spectroscopy Study