Search results for "near infrared"

Global modeling of the lower three polyads of PH_{3} Preliminary results

2009

International audience; In order to model the high-resolution infrared spectrum of the phosphine molecule in the 3 mu m region, a global approach involving the lower three polyads of the molecule (Dyad, Pentad and Octad) as been applied using an effective hamiltonian in the form of irreducible tensors. This model allowed to describe all the 15 vibrational states involved and to consider explicitly all relevant ro-vibrational interactions that cannot be accounted for by conventional perturbation approaches. 2245 levels (up to J=14) observed through transitions arising from 34 cold and hot bands including all available existing data as well as new experimental data have been fitted simultaneo…

Iron-loaded transferrin (Tf) is detrimental whereas iron-free Tf confers protection against brain ischemia by modifying blood Tf saturation and subse…

2018

Despite transferrin being the main circulating carrier of iron in body fluids, and iron overload conditions being known to worsen stroke outcome through reactive oxygen species (ROS)-induced damage, the contribution of blood transferrin saturation (TSAT) to stroke brain damage is unknown. The objective of this study was to obtain evidence on whether TSAT determines the impact of experimental ischemic stroke on brain damage and whether iron-free transferrin (apotransferrin, ATf)-induced reduction of TSAT is neuroprotective. We found that experimental ischemic stroke promoted an early extravasation of circulating iron-loaded transferrin (holotransferrin, HTf) to the ischemic brain parenchyma.…

DISTRIBUTION OF CARBON STARS IN THE GALAXY

2018

A search for new faint carbon (C) stars in the Polar region δ > 55o has been accomplished by obtaining objective prism spectra in the near infrared 550 -- 900 nm on images of CCD camera of Baldone Schmidt telescope of Astrophysical observatory. The positions of stars   having color indices (J – K) > 1.3 mag in Two Micron All Sky Infrared Survey (2MASS) were selected to pick out suspicious carbon stars.Our survey is limited in brightness by J < 10 mag. 24 new carbon stars were found and their characteristics obtained. The correlative relation between Teff  and spectral gradient [757 – 685] was confirmed. Such characteristics as Teff, distance from the Sun, absolute Mk  were obtained…

Near infrared light to promote synaptic resilience to Alzheimer’s Disease neuropathology

Alzheimer’s Disease (AD) is a multifactorial neurodegenerative dementia with no curative therapeutic options. One of the earliest impairments in AD triggering cognitive decline is the synaptic dysfunction induced by the selective targeting and interruption of the synaptic region by the small oligomeric form of amyloid beta (Aβ). Recently, the co-presence of Aβ oligomers (Aβo) and tau oligomers (tau-o) at the synapses has been suggested to exacerbate this dysfunction. Therefore, the development of therapeutics aimed at protecting the synapses from the toxic binding of both proteins at the synapses can preserve synaptic health and cognitive function. With this goal in mind, the present study …

Multispectral Photophletysmography for Evaluation of Cutaneous Flowmotions

2021

Human skin may reflect health conditions. Important and possibly diagnostically potent components of microcirculation are slow flow oscillations-flowmotions, however there is a lack of studies in this field. The present pilot study was devoted to evaluation of multispectral imaging photoplethysmography in determination of different components of flowmotions. Eight subjects were enrolled for the study. During resting conditions video was captured from dorsal aspect of hand at seven different wavelength and flowmotion analysis performed. Results indicate that at the resting conditions neurogenic component along with endothelial are dominant regardless of wavelength, while myogenic has the low…

Design of a portable (CW) fNIRS embedded system

2014

An efficient method for subcutaneous veins localization using Near Infrared imaging

2014

In the majority of the medical treatments, intravenous catheterization is the most important phase in which skilled medical practitioners locate the best vein and perform catheterization process for medication or blood sampling. Due to the different physiological characteristics, mainly darker skin tone, scars or dehydrated condition of patients, medical staff stumbles in localization of veins. This paper proposes an enhanced method which intends to overcome the difficulty faced by medical staff in veins localization for intravenous catheterization. Using the Near Infrared imaging and image processing algorithms a novel approach for veins visualization is proposed. In order to have complete…

Conformational substates of the Fe2+-His F8 linkage in deoxymyoglobin and hemoglobin probed in parallel by the Raman band of the Fe-His stretching vi…

1996

Tunability of Injection Seeded High-Repetition Rate Ti:Sapphire Laser Far Off the Gain Peak

2009

We have investigated a tunability of a high‐repetition rate Ti:Sapphire laser seeded off the gain peak. By applying a birefringent filter, the 7 kHz injection seeded Ti:Sapphire laser system was operated with the average seeding efficiency of over 90% and the output power of over 1 W on the spectral range of 900–930 nm. We conclude that the birefringent filter suited for widely tunable operation of the injection seeded Ti:Sapphire laser system operated at high repetition rate.

Design and realization of a portable multichannel continuous wave fNIRS

2014

A design and implementation of a portable functional Near InfraRed Spectroscopy embedded system prototype is described. In this theoretical and experimental work, we present an embedded system hosting 64 LED sources and 128 Silicon PhotoMultiplier detectors (SiPM). The elementary part of the structure is a flexible probe “leaf” consisting of 16 SiPMs, 4 couples of LEDs, each operating at two wavelengths, and a temperature sensor. The hardware system is based on an ARM main microcontroller that allows to perform both the switching time of LEDs and the acquisition of the SiPM outputs. The performed preliminary experimental tests achieved very promising results, thus demonstrating the effectiv…