1,720,976 research outputs found
METHOD AND SYSTEM FOR MEASURING PHYSIOLOGICAL PARAMETERS OF A SUBJECT UNDERGOING AN OLFACTORY STIMULATION.
No full textMethod and related system for measuring physiological parameters of a human subject undergoing an olfactory stimulation comprising one or more smelling olfactory stimuli, where by means of said system and according to said method a human subject is undergone to said olfactory stimulation by sending said one or more smelling olfactory stimuli to the human subject; one or more physiological parameters of the human subject are recorded; and said olfactory stimulation and physiological parameters recording are synchronized
Virtual olfactory device in EEG and olfactory conditioning task: An OERP study
Full text linkAim of this study is to investigate innovative olfactory applications of cognitive neuroscience in order to improve basic knowledge as well as to develop novel devices for enhancing synaesthetic experiences through olfactory stimulation. We arranged an experiment of olfactive conditioned evoked potentials by analyzing Event Related Potential (ERP) of adult safe volunteers during the conditioning perception of 2 odor stimuli, in an experiment of emotional face recognition task. Specifically, it was developed a paradigm of classical conditioning in which the three types of odors (pleasant, unpleasant, neuter) were conditioned on images of neuter face expression and these results were compared with direct results of olfactory stimulation. The main experimental evidence of our study consists in significant values in ERPs components in direction of a greater amplitude and slower latency in unpleasant condition. On the basis of these results one might assume that an unpleasant odor can modulate, in a cross modal way, the perceptions of emotional and neutral face expressions, and it’s highlighted in an early ERPs component (P1) in conditioning way only for neutral expressions
Optical sensing properties of phthalocyanines thin films in array configuration and their application in VOCs detection.
No full textCODEN: 69FXZK CAN 143:50408 AN 2004:85899
A Multi-matrix E-nose with Optimal Multi-ranged AFE Circuit for Human Volatilome Fingerprinting
Full text linkSince hundreds of volatile organic compounds (VOCs) produced by cell metabolism and released into the blood are excreted through exhaled breath or body fluids, the volatile composition (volatilome) of human samples reflects a subject’s state of health and early signals any abnormal deviation from healthy to disease. The chemical volatilomic profile of biological matrices can be transduced in a digital fingerprint by low cost and easy-to-use electronic nose (e-nose) devices based on gas sensor arrays. The e-noses can be used to aid clinical diagnosis supporting conventional diagnostic methods that sometimes require expensive or invasive medical procedures and delays in diagnoses. In this paper, an e-nose devoted to the human volatilome fingerprinting is presented. The device, code-named SPYROX, adopts an array of 8 metal-oxide (MOX) gas sensors and it is able to analyze response signals from different matrices (multi-matrix samples), dealing with exhaled breath and headspace analysis of human biological samples. While other works in literature neglect the design of the interface circuit, here an optimal multi-ranged analog front-end (AFE) circuit is proposed. It aims to the optimization of the read-out sensitivity which, ultimately, leads to accurate training datasets and, consequently, to high classification scores. Finally, the efficacy of the device is proved by testing both chemical standards and mixtures. As a result, a classification accuracy of 100% is achieved with a linear discriminant model. The experimental results give a proof on the system’s efficacy to the fingerprint analysis of complex gas mixtures, which are typical of human volatilome
Neural-network-driven Electronic Nose Enhancing Artificial Olfaction in Non-invasive Diagnostics
No full textThis paper presents an e-nose specifically designed for non-invasive diagnostics and human volatilome analysis. The sensing technology is based on a 10-sensors array of both commercial Metal Oxide (MOX) gas sensors and custom-fabricated counterparts. Thanks to a versatile pneumatic system, it is capable of analyzing response signals from various sample types, including exhaled breath and the headspace of human biological samples. A neural-network-based model is adopted to enhance the classification capability. The device's effectiveness is demonstrated through experimental tests with both chemical standards and mixtures resembling human biosamples, achieving a 97.1% classification accuracy with 7 prepared test samples. The experimental results, along with the capability to discriminate correctly the test samples in presence of water, confirm the system's efficacy in the context of non-invasive diagnostics and human volatilome analysis
A novel method based on gas microsensors to analyze diesel engine oil contaminated by diluent unburned diesel fuel
No full textAbstract- We developed a novel method to detect the presence
of unburned diesel fuel in used diesel fuel engine oil. The
method is based on the use of an array of different gas
microsensors based on metal oxide thin films deposited by sol-gel
technique on Si substrates. The sensor array, exposed to the
volatile chemical species of different diesel fuel engine oil
samples contaminated in different percentages by diesel fuel,
resulted to be appreciable sensitive to them. Principal
Component Analysis (PCA) applied to the sensor response
data-set gave a first proof of the sensor array ability to
discriminate among the differently diesel fuel diluted
lubricating oils. Moreover, in order to get information about
the headspace composition of the diesel fuel-contaminated
engine oils used for gas-sensing tests, we analyzed the engine
oil samples by Static Headspace Solid Phase Micro
Extraction/Gas Chromatograph/Mass Spectrometer (SHS-SPME/
GC/MS)
Olfactive Event-Related Potentials and Volatile Organic Compound: from Physiological Response to Olfactory Perception
No full textSeveral studies, analyzing the sensory components of olfactory stimuli, highlight laboriousness to estimate a precise stimulation interfaced in EEG and the consequent psychophysiological stimulus effect. Olfactory perception, starting with a breath, could elicit neuronal and cortical responses which could be investigated through Olfactory Event Related Potentials (OERPs). Nowadays no correlation has been examined between brain cortical response and physiological activation through respiratory markers. The purpose of this work is to investigate OERPs linked to breath physiology by using a new technological device dedicated to olfactory stimulation in EEG and a novel sensor able to detect biomarkers through the Volatile Organic Compound (VOCs). In order to record OERPs correlated to physiological effect on VOCs emission, we interfaced VOS EEG (MI2014A001344), a patent olfactometer connected to an electroencephalograph and an electronic sensor (e-nose iAQ-2000, Applied Sensor) for VOCs parallel recording. This condition allowed us to control olfactory stimulations and to relate them to psychophysiological responses. Consequently, we detected the olfactory response to record, for each given single step of stimulation, the EEG, the OERPs components and VOCs responses. The experimental settings allowed us to investigated, through OERPs and VOCs, the olfactory response to a neutral stimulus [Vaseline Oil CnH (2n+2)], and to a natural stimulus of rose characteristic odor (PEA, 2-phenyl ethanol C2H4O2). We recruited 15 safe adults (mean age 25 ±5 SD) non-smokers. Subjects performed a passive olfactory behavioral task during the experiment. Afterwards, the subjects filled the VAS on familiar and arousing stimuli dimensions. A general linear model repeated measure was performed on OERPs. Statistical analysis shows main OERPs results on slow potential components, in particular for P3b on Frontal right lobe (PEA p=.003) (PEA*arousing p=.023) in direction of a greater amplitude vs. control; N4 on right frontoparietal (PEA p=.037); and on right frontotemporal (p=.025) positions; N6 on right frontoparietal position (PEA p=.038) (PEA*arousing p=.009) both in direction of greater amplitude in PEA condition. The control exhaled VOCs frequencies are fitted by a normal distribution (single peak fit R2 = .8), PEA administration exhaled VOCs frequencies are fitted by a bimodal distribution (double peak fit R2 = .9). Exhaled VOCs are significantly different, according to the results of different cortical activation induced by olfactory stimulation. Our study suggests that in smell perception (both in odorous and neutral) we can observe the involvement of slow components, related to the breath of the subject, according to the time of perceptual processing. Furthermore, we connected in real time a given stimulus to olfactory cortical activation, analyzed through OERPs, and breath exhalation, as VOCs (physiological response), innovative connection never yet investigate
Human semen: excellent bioaccumulator of Volatile Organic Compounds (VOCs). (EcoFoodFertility project)
No full textApplication of a gas sensors array to the detection of fuel as contamination defect in engine oil
No full textAbstract — In this work we proposed a system based on metal
oxide gas micro-sensors to estimate diesel or gasoline contamination in different engine oil samples. The gas-sensing
layers (undoped, Pt, Pd, Rh-doped SnO2 , In2 O3 and mixed
In2 O3 -SnO2 ) have been synthetized by the sol-gel method and
deposited by spin-coating onto 2mm x 2mm silicon substrates
equipped by Pt heater on the back and Pt interdigitated
electrodes on the front. The sensor array has been exposed to
no-used and used commercial engine oil samples contaminated
with different amounts of unburned fuel. The results of data
analysis (DWT-based feature extraction, PCA and Gaussian
mixture model classifier (GMM)) showed that different fuel
contaminated used engine oils can be discriminated and
successfully classified by the sensor array
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